Should my crush break up with her boyfriend?

I just met my crush's boyfriend yesterday and he said that I'm a re---- for no reason. I recognize him from way back when I was young and use to do all these bad things to me. I remember asking my crush if she ever get any back up from anyone and she said "no". She also said that her boyfriend would get mad if she went out with other boys who turn out to be friends. They also had some of each other and they were under 18 and I know that's not right because I know that it doesn't really show how much that boy cares about her. I don't want my crush to feel hurt or anything but I think she should get over with that boy or else she will get hurt and have a husband who doesn't trust her or back her up. She mentioned that she had a sad life but never told me it yet and I understand how she feel. Even today she is still suffering from that like today, she text me saying that someone pulled her hair and that made me feel some type of way. Should she break up with this boy sometime soon? Should I tell her everything that boy did way before he met her? Should I give her some space after her break up? I need your answers A.S.A.P.

P.S: She also has a crush on me since a year after we met. We knew each other for three years now.