Okay a long time ago, I saw what was either a movie or a TV show, there was a guy who had some issues, and he was riding on a train with a woman, the guy told the woman that there was no one on the train. At first she is reluctant but then she says okay and he starts hugging her. Then later she visits him in a greenhouse and after that she meets people outside the greenhouse, it explodes with the guy inside.

Your Movie MIGHT be SOURCE CODE (5 years old or so)? Jake Gyllenhaal.