What is happening to me?

I can't understand how and why i can be so cruel and mean? Yet, i'd been forgiven all the time.. I wish i can turn back time and I'll repent for all the things I've done. God had sent me such a lovely and nice person to me but how come i still not satisfied? Maybe I'm too greedy.. And i realised that i had been hurting ppl all the time but they never approach to me and tell me my mistake cuz they don't even mind but i do... I do mind..