What would you do if your boyfriend called you a fat whore?

Get rid of him. I'd be out the door no matter how guilty I may have been. Or may not have been. Out the door never to return. You stuck around for flowers? They're cheap, you can buy them for yourself.

First off, he committed a crime - assault. You not reporting him is giving him courage to repeat and will do so with another chick if you break up (which you should immediately do!) By reporting him, perhaps you can help him through the authorities to get the anger management he obviously is in dire need of. A guy should never EVER strike a chick... end of story (and in reality vice versa). Your actions by staying with him say "Oh please, I love being beaten... perhaps make me bleed out some day". That's usually what this behavior escalates to. Call the authorities and file a complaint and stick with it.

I wouldn't be with any guy that asks me clingy questions and calls me names. If I got one whiff of that I'd be out.

I'd break up with him, contact the police and file charges, and also get a restraining order.