My reaction is all that matters anymore....

I had a situation last night where I did return someone's phone call (which I have a bad reputation of not doing promptly). A person I met wanted to see me, I had other plans as I worked in customer service all weekend and just wanted to be by myself, doing what I enjoyed. The person was irate....that I did not drop everything to be there just because he had limited time to see me in his busy schedule. I hardly liked the anger in his voice....and normally would have felt guilty or bad about myself because I didn't make someone happy. Well, not this time, I told him I did not like his shitty attitude towards me and that I did not have to explain myself or be accountable to him for my time. I am not even in a relationship with him, we were starting to see each other a few times, he became downright demanding that I make an effort to see him when he had free time. I can understand his issues but feel that I am not responsible for his chosen lifestyle. He told me I had no control of my life.....something that I thought about after he hung up on me. It seems to me he is projecting his own shit onto me.
Too bad, the more pushy he became and on top of that putting me down...the more I did not want to see him. I have played this role before and I chose to react very strongly this time. His anger towards me is basically his anger towards himself..................I finally understand this dynamic -and chose not to repeat the lesson....with my own emotions because I don't want to get into power struggles, my strength is silent and doesn't need an outlet through some innocent person.