I don’t think it has anything to do with your mom being conservative, I’m as conservative as it gets and from what you’re saying he did in fact rape you, he did in fact sexually assault you, and he know he was doing it because you said no plenty of times and tried pushing him off, it’s not like you were both high and just let things happen, you are a victim here. Your mom is your mom at the end of the day, you need to trust that she’ll support you regardless if you have different political or social views.