What do you do when you find out that the mother of your partner’s children is crossing the line?

My boyfriend called me the other day to tell me that his ex and baby mama told him she still loves him. This is the third time she’s done this.

He continues to tell her that their relationship is over. He no longer feels that way about her. He also tells her that he loves me, and is happy with me.

I’m glad that he talks to me about this stuff, but it’s hard for me. It’s hard for me to meet this conversation with anything but anger. I feel disrespected by her. I know that anything I confront her with will be viewed as weakness or insecurity by her.

How do you handle this sort of situation?