NC for this but long term poster.
Long story short (hopefully haha) - been with DP for a year and a half. We both have young DCs from previous marriages (not relevant but to give context to our backgrounds).
Due to various family circumstances and some emotional turmoil, we had a break a few months ago for about a month, during which time he slept with someone else a couple of times.
Once we were back together, he continued to see her, which I was understandably (I think) not happy about. He told me that they had been friends before, and he didn't want to ruin that friendship. He felt nothing romantic for her, and sleeping with her was a mistake, and just something that he was trying because he was upset about him and me breaking up.
I'm TRYING to be the "cool girlfriend" but it's making me jealous and insecure to know that he is still spending time with her. I've told him that I'm not happy about it, and I've also found out that he's seen her a few times and not told me about it - i.e. lied about where he has been.
AIBU to ask him to not see her, at least not on his own? I don't want to be controlling, or tell him who he can and can't be friends with, but I don't understand why he wants to spend time with someone that he's previously had sex with? And why does SHE want to be spending time with another woman's partner?
It's really stressing me, and I could really do with some objective opinions. Thanks in advance!