Do you suppose that the world revolves around you? Everyone does to some extent but it's also necessary to be considerate of others' feelings. People are people; we pass by many everyday, few good and few bad, yet they are people who can feel joy and pain. A person, no matter what he or she is to us, is not disposable. It's normal to be self-centered and do things if only it benefits us however it doesn't give us rights to use another person for our welfare and then cast them away without thinking twice. We might even remorse and want to compensate for our mistakes but some wounds can never be healed.
Sometimes apologies don't yield forgiveness because such would be our mistake; we quetch that the person, who is supposed to forgive us, is overreacting but we never wonder whether we would have forgiven if we were the one to bear that wound. We might have even sought revenge.