Bobby's temper catches up with him in Fallen Angels.

Bobby's temper catches up with him in Fallen Angels. During a soccer game, Bobby loses his temper and hurts Sam. This isn't an enemy he's trying to stop. It's one of his closest friends, during something that was supposed to be fun. Then he reads Xavier's concerns about him following his father into the Hellfire Club. Coming straight after what happened to Sam, that gives Bobby another reason to think there's something wrong with him. He runs away. Warlock follows because he doesn't want Bobby out there on his own. That's a fairly important difference between Bobby acting confident and Bobby actually feeling secure. Once he thinks his friends see him as dangerous, he doesn't calmly wait for everybody to talk it through. He leaves. The story starts with him causing a real problem, but his response makes it worse. He decides what everybody must think of him and removes himself before they can work through it together.