Hope, think of this as a war. There will be a lot of small battles that'll hurt, but time is on our side. It's not on the side of the OM. Affairs just don't last. Think long term; months not weeks, years not months.
I expect my wife to move out in a month or so. Live her fun little life while still trying to be a respectable mother (hah!). And then realize that she's not the center of attention anymore. That a 36 year old mother of two, living in a crappy apt. isn't going to convince her boss (married with 5 kids) to leave his wife. Just isn't going to happen. Then she'll see that I'm cooking with gas, enjoying my life, and she realize that:
1. I've conducted myself with class 2. I've made changes that she never thought were possible. 3. I'm a great father, and good provider for my family 4. That I'm still the kind, smart guy she married 5. That she misses all of that, and that the love she once had might be rekindled.
Fantasy, eh? Maybe. She's stubborn as hell, and would probably be afraid that I wouldn't take her back. And maybe I wouldn't, depending on how long we've been apart etc. As Yoda says, "Always in motion, is the future."
Either way, 1-4 still apply to me whether she comes back or not. As for my pain and hurt, this too shall pass.