File for divorce only if that's what you want. Because at this point, I don't think you're going to win, if filing is just a bluff.
My H did it to me. Unfortunately for him, he didn't understand at the time I was ready. I want to save my relationship with him and create a new marriage, but I'm just as prepared for a new life without him.
He seems to understand that now as I see some pretty big changes in him and changes in his actions too.
So, again, do not think this way unless you are ready to carry through with a D.