The Solitude of Prime Numbers (2010) on Netflix

Plot summary

The story moves back and forth between 1984, 1991, 2001 and 2009. Alice Della Rocca is hurt in a childhood skiing accident that leaves her with a limp and a scar on her thigh, and girls at school bully her when she is older. Mattia Balossino, whose mentally disabled twin sister Michela disappeared while he was supposed to be looking after her, is clever and becomes a successful scientist, and he sometimes harms himself deliberately. Both keep apart from the people around them. The two meet as teenagers and become friends, and they lose touch when Mattia takes a job in Germany.