Question: I really enjoy writing anti-hero characters. ones that are so cynical and evil you cant help but love them but I'm not sure I'm doing it right.
I don't think of most anti-heroes as evil. I think of them as having a strong moral sense.
Often, they are characters who have become jaded for one of two reasons.
a) They discovered their leaders were corrupt or incompetent. They feel betrayed by their community, so their response is to reject the community, live as outcasts, and in some cases seek revenge on the community. (A TV example: Malcolm Reynolds of Firefly
. His side lost the war, and rather than accept that he backed the wrong horse and adjust to the new reality, he rejects civilization (Alliance) and lives on the fringe of the 'Verse.)
b) They were forced into situations where holding to their strict values didn't work, so they compromised and now are in the position of trying to do moral things by immoral methods. (A TV example: Detective Gordon on Gotham
In either case, these people are bitter over the fact that the world did not live up to their ideals -- ideals which they are unwilling to surrender.
In many cases, one could debate whether the ideals held by such heroes are really correct, and whether it would be more rational for them to let go and make peace with their communities. But what makes them admirable is their dedication to holding those ideals.
It feeds into most people's secret desire to be proven right.
Of course, there are some anti-heroes who skirt pretty close to the edge of evil. I'm thinking here of Rorschach from The Watchmen
. His saving grace is that the people he wrecks violence on are mostly hardened criminals and sexual predators. Nonetheless, there's no nuance in his view, no room for redemption or mercy. He is as bloodthirsty and ruthless as the villains he fights.
So, another way of describing the anti-hero is that he has too big an ego. He believes he alone is right and the rest of the world is wrong, which is an unlikely scenario in the real world, no matter how smart a person is.
Of course, many of us have experienced being disillusioned by people or groups we trusted. So we get a certain gratification from watching an individual triumph over such a group.