It is paramount to forgive, not for the other person but for yourself. Holding onto ill, bad, negative feelings only harms the holder of these feelings, not the person who you feel them for. We have all heard it, over and over again, but to actually do it, and acknowledge that When we hold onto anger, hurt, and ill feelings, it is like drinking poison, and expecting the other person to die, but it only harms us.
Forgiving and letting go, is a scary thing, it can paralyze you. Once you are brave enough to stop the self hatred by saying NO or standing up for yourself. I still find a way to forgive, the price includes letting go. Why? because most of the people you have to forgive, will not improve or change, so you have to.