I asked my (26F) boyfriend (25M) to stop talking to his ex girlfriend (25F) and he won’t end the friendship. How do I get him to stop talking to her without sounding controlling?

I’ve asked my boyfriend to stop talking to his ex girlfriend multiple times in the 3 years we’ve been together. We’ve had many issues regarding him and his ex girlfriend. She’s obsessed with him and whenever they’re in the same town she will go to his house to hang out with him. She has even flown across the country to hang out with him whenever he was in her town for a week. She won’t leave him alone and he won’t stop talking to her. He says he’s not in love with her and doesn’t want to be with her because she is not good for him. He says he’s only friends with her because she was a big part of his life and he doesn’t want to lose her friendship. How do I get him to realize he needs to cut ties with her? I’ve told him I feel disrespected but he doesn’t care. He says he will always care about her and she will always be in his life as a friend. He won’t listen to me and I don’t know what to do.<br><br>UPDATE: We live in different states but he gets to visit me in my state 2-3 times a year. He used to live with me but moved to a different state for work. We’ve had conversations regarding her obsession with him and how uncomfortable it makes me that she always goes to his house whenever they’re in the same state. I’ve tried to avoid blaming him but I can’t help feeling that he could be the one causing her to be so obsessed. I’ve asked him before to stop being so nice to her but that only made him more defensive. He has always felt the right to say and do whatever he wants and has never cared about my feelings. <br><br>I am in the process of getting a new job in his state so I can be with him. But I don’t know if I can move in with him knowing he will still be friends with his ex.