@snood,
I don't share that worry about Sanders. He's a good guy and his goals are definitely understandable. And no question he's passionate in his take on things. But he's not insane. And he's not mean.
I think it must be very difficult to invest the time and energy and passion required for a presidential run and then, when one loses, to avoid the temptations to resentment against one's electoral foe. But it's really only the shallow and somewhat disturbed type of individuals who hold onto that grudge and allow it to determine future thinking, actions and statements. Bernie doesn't seem that type at all. Surely, some of his followers (some of any candidate's followers) will be those types but that's just inevitable.
Bernie will do his part assuming Hillary wins. Because he is a good human.