a insecure man

How does one go by helping someone out of an abusive relationship? This person use to be so strong, but this guy she dates is so controlling, she cant even sit down without being near him, or even talk with anyone, and to make it so bad she is allowing it to happened too her.  I know it is up to this person to leave, and get out with her life.  How selfish can a person be.  She knows that if he does anything to her the family will attack, but what about "my" family?  Why should we be caught up in a decision that you put yourself in and will not leave?  This person does not want her to talk with her own brothers!  He is so jealous it is unreal.  I dont wanna feel like we didn't reach out to her, but she got to do this for herself.  What you think?