Do physically abusive relationships ever have hope?

My closest friend recently admitted to me that her boyfriend has not only hit her on a few occasions, but has really beat the crap out of her to the point where she couldn’t see her clients for days due to the bruises.

I was floored. We live on opposite coasts and I only had the opportunity to meet him once. I never would have known had she not told me this information. It made me quite angry, because I actually liked him when I met him. She is a very strong, independent woman – which makes this even more of a shock.

They are both in their late 30s. She is staying with him because he is going to anger management classes and they have a pact that she can report him to the police should he “beat her up” again.

She really thinks they can work through this. I am curious if anyone has actually stayed with someone abusive and had success.

I know there is not much I can do at this point besides be her friend, but I am curious if there is ANY hope for their relationship.