Well. If you like to see House suffer and you don't mind a very strong but nonsexual relationship, I recommend these two:

The Contract by diysheep. Surreal, intense AU that has spawned more companion pieces by other writers than anything else in the fandom. Here:

http://diysheep.livejournal.com/16483.html

And The Devil Trilogy by kidsnurse. This is a very medically-focused but emotionally powerful tale written by an author with the medical knowledge to make it work. Here:

http://kidsnurse.livejournal.com/1816.html