am I an asshole?

My man of almost a year and a half has a child. She's a four year old from his previous relationship with his ex fiancé. Going into the relationship I knew he had a child bc he told me and despite what my older sister, friends and coworkers told me about not pursing a relationship with him bc of baby mama drama, I was naive and did not think drama was going to happen to me. He's so different than a lot of men and he convinced me to stop men fasting and give him a chance so I did. It was nice and fun at first (not saying it's not anymore) but all of a sudden his ex started trying to hit on him again and do inappropriate things (stripping down in front of him to show him her weight lost after the baby, coming over on Valentine's Day to file her taxes, ask for him to come pick her up from a party, asking to come over at night to see their daughter whom she has half the week 🤔). I don't know if I'm old school but that is not ok behavior for me nor would I accept it. I verbally told my man about it and how I felt regarding that, flipped the scenario as if it was me and asked how he would feel and so on. Eventually he ended up agreeing to let his ex know the boundaries. I gave him the benefit of the doubt and thought he's new to this bc he's never had to do this before (altho i believe boundaries shooed have been set a very long time ago even with ppl u had a child with). Anyways, he communicated that to her over a phone call and she cut him off seeming annoyed and told him she understands all of that. I knew she didn't and communicated that to him. He always attempts to reach out to her regarding meeting or having a phone call convo on how to raise their daughter and she always ignores his attempts or uses lines such as "not right now I'm dying" and she wasn't but that's how pathetic she is. She's dying but has the time to respond to a txt. She only texts or calls him when she needs a favor. A few weeks later she attempts again via asking to come over at night and uses the daughter as an excuse over txt. I ended up responding to her txt with his permission and saying no then reminding her of those boundaries. She gets mad and starts to curse over txt saying that she's annoyed at him bc he would never talk to her like that and that it's me making him do that (yes it def is. The man needs to set those boundaries and u need to repesct them). And then she starts cursing about me. Eventually after I angrily talked to him my man responded to her and told her that her behavior is unacceptable and she cannot talk about the woman he loves like that. She never responded but still continues to flirt with him over txt, in person I'm sure and over the phone. Believe it or not they have no communication when it comes to their daughter but she will call him sometimes and tell him he's the only person she can trust and talk to 😒not regarding ur daughter though?