He should at least tell us why he's so negative
This is his self-justification:
None of them are friendly to me so I don't see why the forget I should be friendly to them.
It's a circular problem. He's unfriendly to everyone because people are unfriendly to him.
ITT: why people are unfriendly to him
It had to start somewhere, and it has to end somewhere; he's consciously letting things go on this way.