Dear Tinybuddha members

It has been a while that I have posted or replied here on this site. But whenever I did, it usually helped me a great deal to hear the perspective of an outsider looking in.

I will try to keep this as short as I can: My boyfriend, 28, and I, 25, have known each other for some 10 years, through mutual friends. There was never really anything romantic or so going until the beginning of this year. I reached out to him on his birthday (because of a facebook reminder) and we started talking. Pretty soon, we were going on dates and quickly got intimate with each other. Rather quickly, he said he would like to be my boyfriend and be in a relationship. Before being official, we often had great conversations about our ideas of a relationship, our morals about commmitment and being monogamous, so we do see eye to eye in things.

Now about his EX: I have known through our mutual friends that he had moved in with his ex, about 4 years ago. But during that time I almost never saw him. A few times I had heard that his ex had some serious psychological issues.
When we started dating and talking he said very openly that the relationship had been tumultuous and traumatic for both. She would often threaten to kill herself, and a few times he had to pull her back from a window sill. About six months into the RS she told him she had been sexually assaulted or abused (I don’t know the details) and from then on, they weren’t intimate with each other anymore. It got worse and worse, they both made mistakes and treated each other badly. They broke up many times and kind of got back together again. Now to my knowledge, I thought they had been broken up for about 2-3 years, after my bf had moved out of their shared flat.
But as I learned this weekend, their thing wasn’t really over until my bf met another girl before me, last spring (so 2014). I believe he acutally told me there never was a clean break and they were still spending time together until he met his recent ex.

But the shock threw my system off. I have since felt serious anxiety, depressed states and anger towards him and her. Mainly because they now are still in touch, but on a friendly basis. When asked why he is still friends with someone who was so destructive to him, he told me that hey had always had such a bad time together, that now being friendly is comfortable and nice because they know each other very well. This I understand.
He also told me he is in love with me, that he is very happy, that he has never been in a relationship where he wanted to spend that much time with someone.
But: I’m scared that he’s still in that dynamic and that as long as they are in touch, he will be. She was very manipulative and horrible to him, and he of course made his mistakes as well. Which is something she likes to bring up every other time they talk. I guess my question is: what should I do? Sit back and be quiet, just let him figure it out for himself?
Should I tell him (I already did and he feels bad about it) that this is very hard for me? I told him I do not want to forbid him to see her I don’t want to tell him what to do. But that I think he should know why he still wants to spend time with her. And I feel like it’s not healthy for both of them to still be co-dependant in some sort of way.

Any advice, kind words or ideas will be greatly appreciated.

Thank you <3
Helen