General

I think two things.

A) There are treatments for gallstones, including surgery and sonar disruption (or whatever it's called), I think.

She needs to get therapy NOW. Eating disorders are very serious psychological conditions, and they should not be treated lightly. She needs therapy. If she is ever going to have a livable relationship with her body, she needs help getting there.

All I can say is, damn son.

"Give up on FAism?" Since when can people pick and choose what they are attracted to? I suppose a gay man can pretend he isn't attracted to men, and live a lie with a woman, or deny himself sexual pleasure and live his life celebate. I suppose an FA can settle for a thin lady, and in the corners of his mind still crave a robust beauty.

Point is, we like what we like. If you like both thin and fat, no worries. But they title of your post tells me otherwise.

I'm still reading!

The problem with an arrangement whereby you're her "first choice" as and when she's ready is that it leaves you both with the sense that it's not yet packed away with the ends tied up neatly. Unfinished business. There might be more to come. Doesn't that result in neither of you being truly emotionally free to move on?

Maybe you don't want to be. It was just a thought.

Just going to point something out, talking about a relationship that works and doesn't and the messy split you and your ex had probably will not attract many bbws from this site.
Just an idea to think about, not trying to be mean. I really do wish you and her the best, but people are going to read this and see how you acted and make a decision about you.
You seem like a very caring and sweet dude, I hope you find what you are looking for.
Don't change who you are, for anyone. Ever.