I need advice. So there's this girl that my husband was friends with in high school. I've never really cared for her. She texted him out of nowhere and told him she didn't like that we were married because they were supposed to be married, she would invite him and him only to parties and bonfires, wanted to carpool with him to work, and would invite just him to her house but would never want to come to our house. They have started texting again and I've been asking for almost 3 years to stop talking to her because she's a constant flirt, and he won't. I blocked her on his phone and apparently he told her about it. He unblocked her and she would text him and call him asking "lol did she block me again?". We've had so many fights about it and all he says is "I'm not going to let loose of her. I don't see what your deal is." She told a friend of mine that she thinks its funny. But he "don't see the issue?!" What should I do? Do I talk to her, because clearly talking to him doesn't work. Or am I just overreacting?

He also has a history of texting other girls telling them just how beautiful they are.