I've asked it before but I am still lost - BOYFRIEND'S SISTER HELP????

I know I've asked this but I don't want the advice : Wait and/or dump your boyfriend. That's not what I want to do.


My boyfriend's sister hates me. Really hates me. I'm not allowed in her house. She is 23 and my boyfriend is 21. Ever since we started fighting she has called him every day, as much as 3/4 times a day. She asks him to come over every time. He was there yesterday from 3-11 pm, and now they're going bowling together tonight and I'm not allowed to come. My boyfriend has no other friends and he feels like she is his friend and he's going out with friends. It's not the same . He feels guilty if he says no to her, and she guilt trips him. We live together, and I am left at home 4 or 5 nights a week, till late. She said she was sick and had to go to the ER because of stomach pain, so he visited even more (but apparently the pain isn't too bad to go bowling...) I can't tell him he can't see her, he tells me I need to stop freaking out. HOW DO I FIX IT.I've asked it before but I am still lost - BOYFRIEND'S SISTER HELP????
Tell him he can see her once a week, no matter how guilty she tries to make him. If he wants to see her more than that, the relationship is over. The ultimatum may make him think a bit about what he's doing. 4 or 5 nights a week out will destroy your relationship in the long run anyway.