I'm frantically trying to remember fics that I've read where Sam was raped, I know I've seen some good ones! I'll keep looking for you & comment back with those if I find them.

One I highly recommend is this one. Dean doesn't really get revenge as such but yeah, it's great!

Fade To Black by phx69
http://phx69.livejournal.com/34841.html
Roosevelt Asylum was Chicken Soup for a Brother's Soul. Compared to this.

In the meantime I have 2 fics to recommend for your Mental Institution request, both are Sam being the in the Institution:

The Edge Of Madness by Dawn N:
http://www.fanfiction.net/s/3261634/1/The_Edge_of_Madness
Summary: Sam pays a high price after facing off with the Demon, and Dean refuses to lose the last of his family. He is determined to help Sam find his way back.

Further and Further Out by cottonmouth
http://www.fanfiction.net/s/3740163/1/Further_And_Further_Out
Summary: John never disappeared before the pilot episode, so Dean never went to Stanford to find Sam. Two months later and they discover the demon went after Sam after all… Alternate Reality, graphic wincest in later chapters


And this rec is just a general one if you're looking for a good distraction form what's going on in your life:

Finders Keepers by TraSan
http://www.fanfiction.net/s/5549114/6/
Summary: There are some people who just never learned it isn't nice to take things that don't belong to them. Dark fic.


Hope those help!