That depends on how did they hurt you, to what extent? What kind of hurting? Because some minor hurts can be forgotten easily and forgiveable as well.however if its more than enough so i think its better not to forget and forgive, because if you do so, they will repeat the same with others.
Yes, but be really very careful about your self and your family. Mostly just try to avoid such kind of people if you think they can leave you by ignoring them.
Thanks for your words Kienanmi. Thanks God I don't remember those sad days. Fortunately I can forgive and stay in peaceful. Life is too short and I have so much to learn, to do and to see. "What doesn't kill me makes me stronger"(F.Nietsche) and, as I can read, the same is for you Be happy!