Dark Obsession (1989)

Hugo Buckton seems to have it all: He is apparently rich and has a beautiful wife and a doting son. In actuality, though, Hugo is having money problems and is paranoid that his wife is cheating on him. After a boozy night at a party, Hugo hits and kills a woman with his car -- and at his friends' urging, keeps driving. When Hugo starts receiving letters from someone who knows about the accident, he begins to suspect that he has been set up.