I know your sitch because i went through similar circumstances. Is there someone else? Prepare yourself, because it sure sounds like there is.
Also, if she's the one that's unhappy, why are you leaving? Stay in the house. If she wants to acknowledge the matrimonial bond and address the issues at hand, she's welcome to stay. If she's going to be obstinate and simply say it's over, then she can leave. Might seem harsh, but that's the reality of the situation - you are there wanting to salvage the marriage and she isn't addressing anything.
And, as puppy says, do something about the physical attacks!
