Can't remember the title of a movie form the (i think) 80's.

Movie about a kid that is bullied at school, falls in love with a girlfriend but she loves another guy who helps this kid and beats up one bully putting his head in the toilet. If I remember well the kid lives in a train and often goes visit the girl at work and home. Later on she gets pregnant with the other guy who is meanwhile wanted by police and during a car chase he dies. The girl in some scenes is seen in the countryside, pregnant, sitting down near some rocks and crying.
Please help me! I'll try to answer questions if you have them.
Thanks!