What the hell do I do? I have my own ADD to worry about, I know I'm selfish.
Dont for a moment think you're being selfish. It is every persons responsibility to put themselves first. You must take care of your own health & happiness. That doesnt mean being nasty, rude or hurtful to others, something I dont think is a prob with you. You seem to be very caring, esp as you are worried about the weddings you have coming up that you dont want to be ruined
for them.
I agree with momtara, you see your future in your BIL if you stay. I think you know the answer too. I am all for trying everything to make a marriage work, I believe way too many people give up way too fast, but in your case you have tried. I would suggest if she doesnt want to seek therapy for herself (even that may not work as they really need to want to get therapy, not be pushed into it), then you will have done enough & should go. Ultimately it is up to you.
Do you feel like she will change or do you think you're heading down the same path as your BIL?