My girlfriend has cheated on me I think 7 times now in 3 years.
I've felt/seen/hurt just as you have.
I was admitted to Aurora Psychiatric of Wauwatosa for 1 week because I jumped into the local river trying to drown myself. (was actually my paren't s divorce that upset me but it's still suicide)
We're all here for you. This wasn't your fault so don't think like it was.
p.s. I envy the fact that you can throw a punch. In a fight, I'd be about as useful as a pool floaty...