One of my friends is becoming an incel

One of my friends is becoming an incel. He's always been lonely and hasn't had a lot of girlfriends. Early this year he tried to go on a few dates but every date he went on ended badly and he got his heart hurt. He's now woken up to reality and sees that nobody's going to date him and he's going to live a lonely life.<br><br>He's started posting about how the dating system is messed up and how it's based on looks. He's had a few girls show interest in him earlier but every time he wasn't good looking enough for them to stay around. He's now started acting more bitter and resentful and he's started talking about how he has nothing to lose.<br><br>A few days ago we were talking and he said that he wants to do a school shooter. I'm genuinely worried that he's going to do something bad because he's become very bitter and resentful.