@bryancullen142,
There is no reason whatsoever for anyone to wait for a second injury because of allegedly sincere "I'm sorry's". By your logic, it's only good for her to leave him if he gets a second chance to smack her around.
Why, exactly, does she need a second injury (and in her case, it would be her sixth, BTW) in order to prove that this guy is an abuser?
Hint: even dog bite cases don't require so many proofs of viciousness.