What to do in this relationship?

We have been in the ralationship for two year with her. My problem is that nowadays she like to go in a club with friend every Saturday and she come home late around 2am to 3am. I've tried to explain to her that i don't like what she is doing but she doesn't listern. I love her but I'm am afraid that her behavior is gonna end our relationship, because nowadays sometimes I'm happy for her sometimes I feel strassed I feel like I can dump her. I'm no longer happy for her most of the time. Sometimes I feel like crying when I think about what she is doing. I don't know what to do should I dump her or not. I really lover her but I cope with her behaviour. Sorry for my poor English. Thanks in advanced! because nowadays sometimes I'm happy for her sometimes I feel strassed I feel like I can dump her. I'm no longer happy for her most of the time. Sometimes I feel like crying when I think about what she is doing. I don't know what to do should I dump her or not. I really lover her but I cope with her behaviour. Sorry for my poor English. Thanks in advanced!