Is it normal what my father says and does?

My father keeps putting me down. Nothing I ever do is good enough for him. Sometimes he helps me out with important things and treats me nicely and other times he tells me bad things about myself or tries to blame me or make me look stupid. I cry. I cry a lot. It hurts me because I somewhere inside me want him to be proud of me and recognise me but even though I used to get As at school and college, he always had something negative to say that still wasn't right about me. I don't smoke, or take drugs, I'm going into the health profession soon God-willing. I try not to do anything wrong and I'm very conscious of myself because I feel I am always being judged and the internet is the only place I can let go and feel free.

He was an abuser, he and my mum would always fight every day of my childhood. He became so manic that I had to leave to stay with my gran or I would have failed my exams. He became paranoid and started locking my mum up in the house and checking her cellphone. She teaches at a religious school with her sister and he would follow her and make up stories about how she was leaving school during school hours which is impossible and cheating on him. She would never cheat, he's always been possessive. Because he is diabetic, my family said he has some psychological problem, but no one has ever done anything about it. They keep using him to do stuff for them. He functions well enough at work. He is just obsessed with security and feels people are following him. He wasn't obsessed like this in the past, but he used to have a lot of fights and used to always be unhappy with my mum and I. I'm glad they are separated now, but, I'm still sad.

He blames me for not visiting his family, when I am just a kid to them and they never showed us any care when we were going through financial problems. Our reputation has also been affected as my mum told his family how he was wrongfully accusing her. His family is very cold and I never got a long with them. He always praises his side of the family, and picks on the religious things I am supposed to do, which I don't always do because I'm depressed about my situation to care about anything. I left most of my hobbies and my friends and just like to sit in bed all day sometimes. My father is a very stubborn man and he has many flaws, but he only sees mine.