In time I can. Forgiving people is not easy, that is for certain. I however, don't like to hold onto the past. I never forget what has happened, so I prepare myself for the possibility of more disappointment, but I can be forgiving.
Everyone makes mistakes, everyone has their own demons they are battling. People deserve the chance to change or correct their mistakes; and even if they don't, it is best to forgive them anyways.
Like you said; if God can forgive us for all of our sins, then in order to be more like God, we should be able to forgive others for whatever they have done.