My boyfriend and his ex

So, my boyfriend and his ex were together for close to ten years, first as best friends. Since we started dating he told me how he always ended up cheating with her when he tried to be with someone else.

He wasn't speaking with her when we started, but soon enough she made an appearance. I tried to be understanding and even spoke with her about their friendship. Then he hid that they were speaking more. I felt uncomfortable when I found out. I asked him to please stop talking to her, because of how I felt. He said he'd do it. When he did, he stopped being loving at all. When I spoke to him about it, he told me it was because of her. So that if I wanted him to be the same loving guy as before, I had to accept that he wanted her in his life.

I now regret asking him to do it. But I don't know what to do now. Any thoughts?