Misery by Stephen King

Paul Sheldon decides to take an alcohol-inspired road trip from Colorado to California.  He crashes in the middle of nowhere, and his legs are destroyed - but luckily for Paul Sheldon, his Number One Fan has come to rescue him.  Of course, His Number One Fan refuses to take him to the hospital (or let him out of his room), has an illicit stash of drugs, and isn't overly inclined to see Paul's legs heal.

At least Paul's still alive... right?