I didn't find out this fact from social media. I actually did some research on it after hearing about it and it was not from extremist websites as I would never visit such a thing.
Half of the gay men in the UK were sexually assaulted when adults? OMG. This obviously started while children it looks like.
I have no idea what the percentage is of gay people committing sex crimes.
If you are claiming "50% of all homosexual men were raped when they were kids" then post a url to a legitimate source that shows this to be a fact.
HINT: There are none.