cole comments that "nobody else cared about him, so why should he care about himself?" is it true that nobody else cares about him? even if nobody cares about cole, why should he care about himself?

Cole perceives it this way because his anger and self loathing clouds his judgment. There are people who do care for him. Cole's mother does but she has her own issues to deal with first. Certainly Garvey and Edwin put themselves on the line for Cole but it takes some time for Cole to realize this.