My wife and I have not lived together for ten years. I have repeatedly asked for a get, but she refuses unless I pay her a large sum of money. While we were living together she struck me on many ocasions. She refused to stop hitting me and at one point I called the police and she admitted assaulting me to them. Would repeatedly striking me give me the right to divorce her without her consent?
Divorcing without consent is something of a “last resort,” and is reserved for extreme circumstances. Often, the course of receiving the signatures of 100 rabbanim, which permits a husband to remarry without divorcing his wife, is preferred.
In your case, you should of course file for divorce in Beis Din, where your wife will have to explain her refusal to receive a get.
If she is not persuasive (meaning, her claims don’t hold water in Beis Din), Beis Din will instruct you concerning how best to proceed. In general, matters of divorce should be dealt with exclusively through a reputed Beis Din.
Best wishes and good luck with your difficult predicament.