What's the best way for a man to tell a woman he doesn't want to be physical anymore?

You could always smell bad, don’t brush your teeth. Biological body sounds turn chicks off, in a big way. Especially in the company of her friends and family.
She’ll drop you like a hot potato.
Problem solved.

Given that just talking to the woman is apparently out, I recommend catching a disease. A really oozy one. Fatal, if possible - if something’s worth doing, it’s worth doing right.

Fatal is a little extreme IMO. This is a situation that calls for Herpes–incurable, but not lethal. It’s the perfect remedy for what ails the OP’s friend.

Sure. That’ll keep the karmic scales balanced.

“Dear Baby. Welcome to Dumpville. Population: You.”

Yeah, I don’t really understand how this is even a question. Speak the honest truth - deal plainly and be prepared for the worst possible outcome.

Gee, I dunno, MAYBE they have some mutual interest that brought them together in the first place?

But that’s not really dating then. I go out with friends all the time, well, I used to, because we have some mutual interest. But we aren’t dating.

I can not tell you how many people assume that if a man and a woman are interacting they MUST be on a date. Or fucking each other.

Had to deal with that a lot back when I was an active pilot. The area of aviation I was in at any given time ranged from 20:1 men to women to 200:1 men to women - meaning I was frequently the lone woman in a group, my co-pilot was a man, etc. Always this assumption there was something romantic and/or sexual at work. Did they assume that about two male pilots? No. (Although I do in fact know of one situation where two male “buddy” pilots were, in fact, having an affair.) Two women pilots in the same plane? (No, or so rare it never came up in some guys’ experiences)

Also other endeavors.

You and I apparently understand the difference. Many others do not.

Also, I could see a situation where two people with a common interest do start having sex together, but then find out that they aren’t so much interested in each other as their mutual interest. But yeah, it’s a delicate situation. I do agree with the folks who have said “use words”.

Lots of theories. Guess I got what I need to know. To clear up some misconceptions: Sex WAS kind of the point when we (yeah, me) started dating. But … I dunno, I just don’t care to follow through with it. I know I’m mightily stressed out about work, and definitely not as young as I used to be. Something about it just doesn’t seem quite right. I no longer care about sex enough to do it just because I can. I need something more. Or maybe I just want to be alone right now. I feel weird about it, because she IS nice, and IS horny, and it’s hard not to like that in a woman. But I also know she’s sort of hoping this will go somewhere, and I know it definitely won’t. She tries to downplay her expectations and not scare me, but I can see the writing on the wall.

Hold on, are you referring to me when you say “you” here?

Oh, man. This just got more serious. Dude, tell her straight up. It’s not kind to keep her on the hook.

Hey, there’s nothing wrong with not wanting to have sex if the woman expects something more from the relationship. It’s good that you realize that beforehand. Most of my experiences after my divorce seemed like just two people having fun, until the “wants more” part comes out and somebody gets hurt.

This, exactly.

If they aren’t compatible on a level this serious, they should end it. Period.

Not tonight, I have a headache.

This is a form of a breakup because the other person seems to have a desire for more of a relationship. Some people can handle friendships after relationships, others can’t.

After you tell her that you just don’t feel it’s right, let take the lead if she wants to be (and is capable of being) just friends. Certainly don’t push it.

Yeah, I’m assuming you can interact with a woman in some fashion - working on a job together, having a conversation about a particular topic - without an automatic expectation that sex will ensue.

I have a similar issue with my relationship. I am loosing interest in her sexually. Physically I am attracted to her but I am not at all happy with the sex. I very much enjoy her company and I have to admit I feel very good cuddling with her at night when we sleep. My issue is pretty simple, I like to take things slow and easy and stretch it out for a good while while she seems to go from zero to 60 in about 2 seconds which I find unbelievable and a major turnoff. It has gotten to the point the last couple of weeks where I don’t seem to have any desire to want to make love. At 70 years old it takes a bit to turn me on and it doesn’t take much to turn me off. I have been fortunate throughout my life in this area until this past year. I have been with 4 different women all of whom I liked ok but none of them really turn me on. I believe foreplay starts hours before you go to bed, a few kisses here and there, sitting close to each other while watching TV, giving the lady a neck massage etc, just more interaction. These dam cell phones, social media and games piss me off. I find it hard to sit next to someone playing a game for 3 hours and then go to bed and suddenly feel all turned on, it is fake and a turn off.

Well, this sounds to me that it’s not just about sex. It’s about a basic imbalance of what you both want (or don’t) from your relationship. You can’t see it going anywhere, she hopes it can, you owe it to her to stop stringing her along.

TBH that sounds more like the issue is what follows later rather than not wanting to be physical now.

I’d suggest you make The Talk about the later rather than the former.