We lived this as well. As awful as it is, you can’t protect her. She has to be the one to decide to leave. They leave and return over and over, hopefully it finally sticks, but how many times can you be part of it? DV shelter will give them the best chance at leaving for good. When they do try to leave is the most dangerous time. If she’s at your house, he knows where she is, and it puts you in danger.