flatbusher: This is very difficult. Let me relate a story that once occurred to me.
Someone once wronged me terribly. I was very hurt and I honestly told him that I wasn’t ready to forgive him yet. This happened in the winter. About 8 months later, Rosh Hashana rolled around. In the weeks leading up to R”H, he asked me for Mechila three times. I honestly told him that I wasn’t ready to forgive him yet. I thought that was enough.
He then brought a Minyan to my place of work to declare in front of them (and me) that he tried to forgive me but I refused. He said that that’s what it says in Shulchan Aruch (which it does, if you read it Kipshuto).
The point is, he failed in his attempt to ask Mechila and he publicly humiliated me in a misguided attempt to fix it.
Mechila is rooted in humanity and human emotion. You should do your best to honestly forgive the person, but it takes time. Try to move on and the Mechila will come in time. It’s not true Mechila until it does. And when a person (either the one who did the wrong or the one who was wronged) doesn’t understand this, disaster can result.