My boyfriends ex is always concerned about our relationship. she stalks my social media accounts and will text me if I post something that she thinks is about her. my boyfriend and I broke up for a few days before and that night he went and stayed at his ex’s dorm he swore to me that they didnt do anything except smoke and play board games but I really have a hard time believing it. also his ex texted him one time and asked if I was with him and he said no and she asked if she was good at having sex and if she was the best he ever had and he told her that her and I are tied and then said “but its been a long time so idk you could have gotten better👀” I woke him up asking him about it and he said that he didnt want to seem like a dick by not responding. I told him that he could have responded differently and he doesnt see any wrong in what he did. what should I do? is it wrong that im so insecure about him going back to his ex?