Welcome back crazytooth! What @nelliebly said.
As to this:
You are under no obligation to have a next time.
There is nothing you could possibly say that will do anything other than vibrate some hot air in the room. You may as well be speaking Martian for all the impact any word will have on your Mom or, far more importantly, your Mom’s relationship with you. You might as well be lecturing your dog on quantum physics. At least the dog might listen politely; Mom won’t even do that.
The fact you’re experiencing increasing anxiety with that thought is your subconscious telling you that having that conversation is not in your best interest. Listen to it.
If talking to her is not to your benefit, why are you planning on doing it? Because of your long-standing bad habit of doing things that are bad for you that are intended to benefit your Mom.
As I said in a previous post, breaking this lifelong habit is hard. Very hard. You will doubtless backslide a bit here and there. So don’t be too judgmental on yourself when that happens. But any time you can identify a backsliding event before you do it just run the other way. That’s pretty easy.
Oh, and tell your husband to cut off all contact as well. That’s simply daring the camel to come halfway into your tent. He needs to be on your team 100%, not playing 50/50 or “referee”.