Sociopaths live based on a reputation they create. It's a false reputation, but it's one of the only ways that they can continue their controlling lifestyle. Confrontation, especially public confrontation can damage or shatter that reputation, causing damage to the sociopaths lifestyle as a whole
Revenge?
Yup
they are angry that they cannot feel human emotion...like all the humans they see. they are dead inside. they are almost like a machine-human. they know somthing is wrong with them but they dont know what because they have no CONSCIOUS
Riahanna ^^ she makes him very angry
Rovio makes Angry Birds.
Pollution makes the Earth angry. At least, in a metaphorical sense.
Hormones
Martha Stout PhD. states in her book "The Sociopath Next Door" that "if someone makes you feel sorry for them while continuing to hurt you on a regular basis, chances are close to 100% you are dealing with a sociopath". I would imagine this would especially apply to boyfriends.
Adrenaline
being bullied
No. It doesn't mean anything to him/her. That is what makes them what they are . They have no feelings for others and they don't care about others.
My older sister is a sociopath.