I think that's count as forgive, especially since he wants to get along with her.
It's a 50/50 I'd say. I personally feel that he saw that getting revenge wasn't making him any happier, and hitting her the one time he did just made him more miserable. Not to mention, she openly welcomed and encouraged him to retaliate.
His anger has nowhere to go. He decided to set the baggage down and leave it behind. It isn't serving him.
At least, that's how I feel it. I empathize pretty heavily with the story due to personal reasons, and for some of us, there comes a point in your life where you realize holding on to grudges and anger is literally poisoning your soul. It's pointless.