You are not a Therapist there is no way for you to know what is really going on.. Yes you are hearing just her side.. and from what you have posted she seems very needy and unstable and if she is being abused she has to get help you cant do that for her.

Its Human nature to want to pick things apart and understand how people are , why they do what they do.. But you are wasting time and brain cells wondering whats going on with her and HER relationship with the guy. He could be a good guy and she is abusing him.