Staying the night with my so

So the thing is: I live with my mom she is a Christian/ catholic person and she haves her house rules which some of them I respect. My boyfriend is often asking to stay the night with him (at his house) but I always ignore it because my mom won't let me. And we argue about it yesterday. I mean I could do it because I don't see that as a disrespectful thing to do but my mom thinks it is. Do you think it is okay or it is not okay?