Is it normal to hate my birthfather and claim he isn't my real dad

Okay. I'm about to tell you a true story. I'm a 18 going on 19 year old teenager that has been raised mostly by a single divorced mother. She divorced my "father" back when my younger twin brother and i were perhaps 3 years of age. All Monty (that's his name) ever did was get our mom pregnant with us. When that bastard wasn't being a lazy good for nothing he beat our mom, tried abusing my brother as a baby, and drank. I have the GREAT misfortune of having that asshole's last name (Rackley). Personally, if i have had a saying in the matter, i would've chosen to be born and raised a bastard than to have that monster's name. No, i was never abused but i bet that if mom had stayed with him, i would have been. I may share DNA with that prick but Monty is not my father. I do have a real father but it's certainly not Monty. Monty WAS NEVER my father. I cannot tell you all the name of the man whom i claim to be my REAL dad. You probably wouldn't believe me or understand it if i told you.
Please don't tell me that a birthparent is a real parent. That isn't true. Just because a man gets a woman pregnant and a woman gives birth does not make them parents. A real parent is someone who is actually there for his/her kids and loves them unconditionally. In a word a man or woman that would give up her or her life to save his or her babies. That's a real parent.Anyway, that's my story.