jazzguitarman:

Your girlfriend is having sex with someone else. She might have a STD and she doesn't wish to give it to you. The other guy is either married or a deadbeat which is why she still keeps you around.

Fact the fact buddy; She isn't into you anymore and move on.

I agree she may not be into him anymore, but I'd bet she's not screwing around on the side, based on his description. Something has caused her to dwell on her past events. He may have innocuously said or done something that gave her a flashback. She may have heard that someone who hurt her is ill or died, which triggered a feeling of guilt in her for not forgiving them. It could be 100 different things.

The OP has been more than patient, it sounds like. He needs to ask her to get professional help. If she refuses and he stays, she'll eventually drag him into her pit with him. He shouldn't condemn himself to a life of completely non-sexual living, and by that I include the normal signs of affection two people who care about each other share. It would be different if she had changed in some way because of something new, a serious physical illness, a mental illness that she is willing to seek help for (and didn't appear to have when they met), a traumatic event like being raped which occurred recently. But if he has done nothing she will tell him about to bring this on, he's done his part, and doesn't owe her anything if she won't try to help herself.

They didn't have a healthy beginning to this relationship. He was hurt and looking for someone he felt safe with. Same with her. However, he got better, and that itself may be why she seems to be worse. She no longer has anyone she can commiserate with and/or feel superior to. He no longer needs her to "save" him, and she isn't coping well with that.