You can Google it, but from what I've seen the stats are not very reliable, since like domestic violence among straights it's assumed to be an underreported problem.
I was a victim of gay physical violence once, in 2001, that I wrote about here before. But I'll never be anybody's victim, and I began making plans to move out the same day it happened to me. I wouldn't have waited even a day but my options at that time were limited.
But my case was an easy decision, involving my physical injury. I do see partners, gay & straight, who inflict verbal and psychological abuse on their mates. And the victims seem to adapt to it over time, and come to accept it, even defending their abusers, and that's a kind of domestic violence that's much more insidious.