True, but again, both often went out of their way to be unlikable jerks to the rest of the camp . . . but the difference is the intention.
Frank was a really messed up person, mentally and psychologically, he really didn't know how to be a decent person because he grew up in an abusive house, with a brother who always picked on him and called him names, and a father who "pretended to like him." No wonder he's such a momma's boy, because his mother was apparently the only one in the family who treated him well. Frank's social and people skills were tragically skewed.
Charles, on the other hand, wanted nothing to do with anyone else in camp, mainly because he didn't even want to be there (nor did anyone else for that matter), and as he said himself, he'd blot everything out of his memory as it happened, because he knew he'd never be able to forget them, nor the people. He had an aristocratic upbringing, and expected the finest things in life - he saw everyone else in camp as being completely beneath them, and as such, he wouldn't form any kind of bond with any of them because he had no use for them.
And yet, both were strangely drawn to Margaret, for different reasons. Margaret was clearly just a plaything for Frank; and it was clear the writers tried to make Charles her new love interest in the beginning, but thankfully they steered away from that direction.