Finally asking for help:

[late30s]

I also have to figure out how to say that I don't want to go to the beach with her and her friend with the kids. I just can't do it. She would stay with her friend and I would have to drive down with the kids, get a motel, take care of everything, pay for everything, and then just hang around while they all do whatever. That's not who I am. I won't be a doormat anymore.

If it were me trying to convey this message to my W, it would go something like this.

"W, I can't join you at the beach this time. I'm not comfortable with it."

From what I have read in your previous posts, she may very well press you for information about why you can't go. I'd simply stick to it isn't something you feel like doing right now.

I don't know if you receive similar reactions, but generally speaking if I try to tell my W the real reasons why I don't want to do something and any part of that reason is how I believe she'll behave toward me, it becomes time to get the spew jacket out.

Not feeling like it is an acceptable reason for most people.

Good luck, Solo. Keep focusing on you and just take it a day at a time.