My boyfriend broke my trust, how can I take him back?

If you really believe that he can change, and that he can be the person you need him to be if he gets help, then forgive him. However, if you dont think you can trust him ever again, and put faith in him that he wont do this again, then maybe you already know the answer to this. The fact that he said he has to convince himself to stay with you that only makes me think that he has a fear of being alone. I can't say what he is really feeling, but that is what it sounds like. He left because he didnt want to be with you, then realized he doesn't want to be alone either. Its your choice of course if you want to work things out with him, but I think you should be careful, and before you take him back, make sure he is getting the help he needs. Good luck.