Bf’s ex tried coming back into his life

I don’t know how to properly cope with my anger towards my bf’s ex. I am going to therapy and this is a topic we will discuss in my next session (tomorrow) but it would be nice to hear other ladies experiences.

My bf, who I’ve been with for a year and live with has an ex that he had broken up with a year before him and I even met (so at this point it’s been 2 years). He was best friends with her for years before they started dating long distance and based on everything I have heard from him and his friends she was very manipulative. When he would come home to visit her she would ditch him to go to parties and he tried to be a good person but he was naive and she ended up cheating on him 3 times, the very last time is when she was caught and everything came out. He broke up with her obviously bc at this point she was dating him and the other guy. She was all heart broken of course but continued the relationship with the other guy while also spreading rumors around the entire small town about my bf, trying to cover her name for being a cheater.

A year passes, he stays single, focuses on himself, goes to therapy, and meets me. We start dating and all of a sudden when she finds out she tries popping back into his life but he cuts it off real quick. Then a couple months ago she reaches out to him again (he is friends with her brother), she calls him actually(yes I know he shouldn’t have unblocked her, this is something him and I have discusses already) tells him her bf and her broke up, and she misses him(my bf). He told her they could never go back to being friends like before, that could never happen and it would be wrong. She apparently was sobbing telling him how much she missed him and trying to guilt her way back into his life. He told her he was happy with me, lives with me, and then he blocked her.

I have so much anger and resentment for her. I am normally a very calm and forgiving person but she just makes me so angry thinking about everything I heard about her and how she tried to get back with him(or at least back into his life) while with me. I know I should move on. She is blocked, and not a threat. But every once in a while this anger just fills my body and I want to actually confront her and ask her what the hell was she thinking? To make things worse, I am dealing with my own insecurities which are getting better with time, but I had so much jealousy towards her. She got the better version of my bf. She actually messed him up pretty badly and although he does his very best to be a good bf to me, I see those trust issues creep back in every once in a while. All I can do is love and reassure him. But man I hate her so much for screwing with his head as bad as she did while they were dating and making him feel like everything in life was his fault. I just want this anger to stop. I don’t even know why I want to confront her but I do SO badly and I feel like that’s the only way to move past this, but I know it’s not a healthy option and I’ll just look like a crazy gf.