The Rain People (1969) review

Early one morning, Natalie Ravenna (Shirley Knight) leaves her husband Vinny (Robert Modica) and starts driving out west with no set destination, phones Vinny to tell him she's pregnant, picks up mentally-incapacitated hitchhiker (and former football player) Jimmy Kilgannon (James Caan) and then spends the rest of the time attempting to get rid of him.  This is trying to be an existentialist road movie - Dennis Hopper's Easy Rider was released the same year - that represents the mood of the late 60's, except Natalie (who, for reasons unexplored, sometimes refers to herself in the third person) is a contemptible individual who only really cares about herself: she taunts Vinny by suggesting she might have an abortion, treats Jimmy like he's garbage and later ditches him so she can have sex with police officer Gordon (Robert Duvall), who lives in a trailer and is abusive towards his young daughter Rosalie (Marya Zimmet).  Both Duvall and Caan are outstanding as a dual "reality check" for the ungrounded Natalie, although the film ends inconclusively, with Jimmy acting as the "sacrificial lamb" for her narcissistic whimsy.