Even if your man is only five ft. six, the image of men as abusers is deeply ingrained in the public imagination. Abuse is a great lever for you. No risk and great reward. The poor guy can find himself fighting a criminal charge, a divorce action, and custody action all at the same time. Nothing can get you a favorable settlement better than letting him know you can bleed him to death.
Abuse is real easy to pull off.
The next time you and he have words, call the police and file a report. For added effect, this process can be repeated to show a trend towards violence. As an added bonus, after a couple of run throughs you might be able to get the guy so steamed up he will say or do something stupid while the police are filling out the report. Nothing will directly happen from the abuse itself, but those police reports will come in handy later on. If the guy is still living with you while you wait to get the house, it's nice to know you can take a free shot on a moment's notice by picking up the phone.