Forgiveness part 1

Forgiveness has become a very important issue recently. Not just for myself, but for some of my close friends too (for different reasons).
So - are there different levels of forgiveness? Are some easier than others?

I've been thinking about this alot.
It seems that 'small' hurts are easier to forgive than 'big' hurts.
Hurts that I see as accidental are easier to forgive than those I see as deliberate.
It's easier to forgive if there's an apology (or at least an acknowledgement of the hurt).

So how do you forgive someone who has hurt you repeatedly and deeply, who will not acknowledge it, and you have to keep seeing regularly?

That is the killer question my friends and I are struggling with at present. Answers on a postcard please....