How do I make her to break up with her boyfriend?

If you are interested in someone who is in relationship with another person, you should make your feelings known to her. However, you should also tell her that you understand that she is in another relationship at this time. You don’t want the message to her that you have feelings for her to come across like you are a stalker.

If you try to break up her and her boyfriend, only resentment will come from this. She will eventually realize what you did and will have problems with that. She may even try to get back with this boyfriend because she would blame you and not the boyfriend for the break-up. Making your feelings known without being pushy or manipulative is the best way.