She knows you will help her. She doesn't want it yet...maybe never. It is HER life to lead however she sees fit. If she truly hated it so much, she would be willing to do whatever it takes to change it. The fact that she continues on is proof that she is not yet ready.
Stop trying to control the situation. You say you understand you can't, yet you still try. Just telling her "one more time" that help is available is just you attempting to control. Trust me, she knows.