Hi Im looking for any fics where Spike is sick with an illness. Also looking for fics where he has a personality disorder like OCD or anxiety.

Hi,

There is this great story, still in progress, "Blood of the sire" by BuffyMeetsSpike. It's on Bloodshedverse.

This story takes place in Season 6, after As You Were. Spike kills a demon in a bar brawl, and his brother exacts revenge. Despite their rocky relationship, Buffy undertakes an arduous quest to save Spike's life. Will Buffy, Spike, and their relationship survive the experience?

The English Patient by Pipergirl at Elysian Fields is a great Spike is sick fic.