I'm going to emphasize this: never, ever get back together with someone because they are guilt tripping you. It's an emotionally abusive tactic, and demonstrates a lack of respect for you as a partner and as a person. If you don't feel like things are working out, don't get back together with her. You aren't "obligated" to do anything, especially if it's causing you emotional pain. That's your brain trying to tell you something, and it's important to listen. Things aren't going to get better just because you get back together with her; I promise, something else will come up down the line and it will create the same problems. She's not going to change just because you take her back, so you can't really expect anything different from her. I'd say if you feel it's done, leave it at that. You gotta take care of you first and foremost.