Am i being unreasonable for not talking to or seeing my Father in almost over a year?

I've had a weird relationship with my father as well. He is an alcoholic, my mom left him because of him being abusive and the drinking. He has been so mean to us through out the years. Especially to me, I'm the middle child and both parents has always favored my older and younger sisters, so i've always been a little distant. I never felt comfortable talking to them about personal things and such. Anyways, he would call me a and accuse my younger sister and I of stealing money from him on multiple occasions. All because of the alcohol. We'd go months without seeing him and then he'd cry and complain to other people saying he misses us and all this and that so we'd go down to see him. We kept trying and he always acted oblivious to the way he had treated us, as if they alcohol was his excuse for forgetting what he had done to us. Now that I'm older I call him on occasion and try to see him on holiday's and such. I just figure I'll be the better person and if anything was to happen to him, I won't regret not trying to have a relationship with him no matter how vile he is. Just try not to fully invest your emotions into him or you will get hurt over and over. Good luck with you dad!