William Marston, creator of Wonder Woman, had a polyamorous BDSM relationship with his wife and another woman. If you read the early WW comics, the influence of his private life on his comics is pretty transparent.
Now, on to more-philosophical and less-practical discussion.
A lot of this depends on your friends - what kind of people they are, what kind of relationship you have with them, and what they’re doing. The question seems to be how much of the problem is their behaviour and how much is your feelings and perceptions.
You’ve known these people a long time and are apparently fairly close, from what you’ve said.
Are they the type of people to be “flaunting” this situation just to troll for outrage or attention? If so, then you’re probably right to be unhappy with them dragging everyone else into their personal dramas - but I’d think you’d be used to that by now. If they’re not that type of people, then why would you assume that’s what they’re doing now?
I know you said that you felt like they’d been hinting to be asked about this. Try to be objective for a moment - is that really what they’re doing, or just what you’re perceiving when they talk about their new relationships because you’re uncomfortable with the idea?
As an example, I remember talking to my mom one time about gay couples. She couldn’t understand why there was a problem - they just didn’t ever have to mention anything about their partner and no one would know. When I asked her how often she mentioned her husband/family at work in casual conversation (we watched tv last night, we’re going to the in-laws this weekend, hubby is sick, I made a great new recipe for dinner & hubby loved it, a quick kiss goodbye in the car, etc.), she realized that what she had been perceiving as “flaunting” the relationships was really just people acting normally. The difference wasn’t their behaviour, it was her perception.
Are your friends truly being creepy, for instance wanting to tell you all about their new sex lives, or are they just happy about being in love and want to talk about it? Yeah, it’s annoying when your friends are head-over-heels, but you don’t generally ostracize them for it (do you?!?).
It sounds like the PDAs are well within the bounds of acceptable behavior for someone with their love interest. I think you said that their behavior isn’t anything that would cause problems if it were, say, between two people dating in a new relationship, and acknowledged it wasn’t the actual PDAs as much as the poly concept (for lack of a better word). I’m going to guess that if your old friends were single and showed up with brand-new lovers and did the same thing, you might roll your eyes a bit, but wouldn’t be squicked out by it.
Is each of them only being affectionate with the new lovers, or do they engage in the same behavior with their original mate as well? Are they people who have always cuddled at these events, or is this totally new behavior?
I can easily see being uncomfortable with radical behavior changes - if they’ve never snuggled before and just started now, then it could be trolling for attention (or it could be NRE - see below). If they’ve always held hands with each other, and don’t at all anymore because all the attention is on the new relationships, that’s scary because it can damage the original marriage. Unfortunately, there’s not much that you can do about that.
There is a phenomenon in poly often called New Relationship Energy (NRE), which is just what it sounds like, and is something to be careful of. It’s very easy to get caught up in the giggly, fluttery, hormone-washed fun of a new relationship (just like single people often do), but you can’t let it overwhelm your existing relationships without having problems. OTOH, you can just enjoy the fun feelings without taking them too seriously or too far. Since you don’t see these folks day-to-day, it’s not really possible for you to tell which is the case here.
How long have they had these relationships? Is it possible that they’ve been going on a while and you just didn’t know about it? Or is this a recent fling, in which case you’ve certainly got grounds to be wary - just as you might if you had a friend that suddenly turned up talking about marrying someone they met three weeks ago. It does sound like it’s a bit more serious than just a quickie fling if the new SOs have moved in (or a reasonable facsimile thereof). While it may or may not work out in the long term, it certainly sounds more like a serious relationship than just new sex toys.
At any rate, just wanted to give you a different viewpoint to work with. I hope it helps you think about your situation and figure out what’s what and where you want to go from here.
As you may have guessed, I’m in a poly relationship and have dealt with many of these issues. FTR, we rarely tell people we’re poly. We just go about our normal routine and see if they figure it out. However, we’re not big on PDAs beyond what’s normal in our crowd, e.g. hugs & quick smooches, maybe a little cuddling/back-rubbing - but those behaviours occur between everyone in our crowd, not just within relationships, so it’s not at all obvious.
IOE (in our experience), those people who can handle the idea of poly usually realize what’s going on pretty quickly and will ask (either us or our friends) to clarify. Those folks who can’t handle it can take years (if ever) to figure it out, or at least to admit to it. It’s been very funny, and sometimes surprising, to see who falls into which bucket. People will amaze you.
If you have questions that you think I might be able to help with, please feel free to ask.* I’ll answer (or not) as I will. 
*That’s an invite to GND. I skimmed through this thread and have no interest in dealing with a bunch of obnoxious, hateful assholes. Please feel free to tell me what a degenerate, disgusting person I am, and that my relationships aren’t real, and how evil my family is. Just don’t be surprised when I ignore you.
redtail23, your kindness is much appreciated. If I think of any new questions to ask, I’ll gladly look you up.
But then how will we have an up-to-the-minute update? 
redtail23: Outstanding.
I’m not sure how I feel about it personally. I’ve known polyamorous people and it never seems to end well, which is not to say that it never can, just that it doesn’t often.
I’m just not really sure why it wouldn’t qualify as a relationship. From what I’ve seen from people genuinely committed to the idea, the relationships aren’t just sexual, and other than the jealousy issues that can develop, are really not distinguishable from any other kind of romantic relationship. I’m the monogamous sort, but objectively I don’t think monogamy is all that special. Marriage is only important because we give it meaning, not because it has inherent meaning.
I don’t really see the problem.
Their PDA’s have been limited to hand holding and cuddling. Just the kind of thing that might help comfort and reassure somebody in a situation where everybody else is likely judging them.
OTTOMH I know two poly couples. In the first, he is monogamous but accepts that she is not. She has a boyfriend of many years who is also friends with the husband.
The second couple are both poly and are looking to form a triad in which all three people are lovers and share in the relationship equally. They have been together for OTTOMH almost a decade now.
The word for a guy like this is “doormat.”
Now, Now…she could simply have an overpowering superpussy like the other woman posted about above who not only had a husband and boyfriend, but a boy-toy.
Even you have to bow down to such power.
If he’s happy, then the word for him is “happy”, which is a lot more than most people seem to end up with.
Accepting it doesn’t mean he’s happy.
Mine is another suggestion to sit down and talk to them frankly and honestly. Personally, I don’t like hanging out with people in situations that bother me about as much as I don’t like hanging out with people who I know are not being authentic and true to themselves. Hanging out with people while not being authentic and true to yourself isn’t necessarily pleasant either, so your friends might also feel quite differently about continuing on the same friendly trajectory if they knew that they had to follow rules of engagement while in your presence.
It seems that there is obviously something to be reconciled, the question is what and how. Maybe you won’t socialize with them as much in the same way anymore, but you manage to stay some level of friends. Maybe this will prove to be a catalyst to completely end the friendship as you have known it. Maybe you will find that your mutual friendship is resilient and flexible enough to continue just as strong as ever and just be a bit different than before, with a few more moving parts. Moving parts who (as others have suggested already) you might find yourself liking.
I have no idea what the future holds, nor am I in a place to judge any of the possibilities as better or worse than any other, but I do believe that talking it through with them is the best way to make informed and authentic choices about the future of the friendships.
Fine, you just show me your psychologist license, and some proof that you interviewed him, and I’ll take your word for it.
People are happy under and amazing number of circumstances. My sister is happy with her husband, who I find to be frankly grossly obese and - probably worse - annoying. But she loves him and if I’m slightly appalled by the situation, that really isn’t her issue, and I shouldn’t try and make it her issue. I care about her, that doesn’t mean I get to define happiness for her.
A friend is married to a woman I cannot stand - what’s worse, my husband tends to treat her with veiled contempt. But they’ve been married for a long time, and once again, it isn’t my job as someone who cares about him to define his happiness. I don’t see him nearly as much as I’d like to, unfortunately. But I believe he is happy with is choice of a spouse.
Perhaps these people are just accepting their spouse and really AREN’T happy…but it isn’t terribly respectful of them to take them at anything but their word. They can get out if their marriage isn’t giving them enough. Apparently, it is.
Saying they must be happy because they don’t leave is a pretty feeble argument for happiness.
They’re happy because there’s no other way to tell happiness beyond self-reporting.
How do you know gay people really love each other? How do you know that gay love is equal to straight love, and that it’s not really just about the sex?
Ultimately, you just have to trust that people know what they’re talking about.
I’d think of it in terms like this:
People who are in their 50s now remember when there were people who were openly racist, and they find racist people to be detestable. And yet, these same people in their 50s may very well be openly homophobic. People who are currently in their 20s have grown up to think that homophobes are detestable, and yet they probably think that polamory is gross or even immoral.
But, the reason why black people became acceptable and homosexuals became acceptable is because some people realized that there was no underlying rationality in that bigotry. They spread that idea via political protest, popular fiction, and other means and children and youths were able to be exposed while still in their formative years and accepted it. Most of these children probably didn’t actually work through the logic so much as they just grew up exposed to the idea that “Black people are alright!”. It was a specific push that worked for that specific item.
Transforming your social outlook late in life is hard. But, ultimately, you should be able to analyze it rationally and if you can’t find any logical reason to think that they’re actually somehow in the wrong, then simply they aren’t in the wrong. You are. You’re an old bigot who can’t, won’t, or hasn’t yet changed.
They are happy enough that they are not taking action to change their situation. And if they say they are happy, who are you or I to say “oh, no, you can’t possibly be happy in those circumstances.”
Doc didn’t say this guy said he was happy, just that he “accepted” it. Don’t insert facts that aren’t in evidence. We do not have self-reported “happiness.” We have a second hand report of “acceptance.”
When was it entered into evidence that this guy says that he’s happy?
Women stay with batterers and womanizers too, you know. Calling that evidence of happiness is beyond specious.