20 years or so old now but this uk movie is one of the very best ( if not best) portrayals of ocd around. It manages to show the mental pain behind the compulsive behaviours. Makes me feel joy, sadness, hope and most importantly reinforces my 12 step recovery.
Good more recent ocd portrayal is the main character in the show Girls. 1 or 2 episodes in particular. Also manages to capture the mental pain of Obsessive thinking.