It wasn't really a case of being "disowned"; I don't think they ever claimed ownership of me to begin with.
My dad never talked to me - and I mean never, ever. He was home every evening and every weekend but not once did we ever have a two-way conversation, from the time I was born until I was 30, when he had advanced Alzheimer's and could no longer talk. On the rare occasions that he spoke to me, it was, "Go mow the lawn. Go wash the car." Never an actual talk. He completely dropped the ball on every opportunity for bonding - showed no interest in teaching me to throw and catch, or drive a car, or shave, or any of the things that dads are supposed to do with their sons. Hell, he never even so much as asked, "How was your day?"
My mom showed no affection to me at all. Remember those bumper stickers that said, "Have You Hugged Your Kid Today?" At my house the answer was No, every day. I literally have no memory of ever being hugged by my mom - and I can remember word-for-word conversations from when I was five (they usually involved me being wrong). I was in my late 40s when I informed my mom that my eyes are hazel, not brown (not even close to brown); apparently she'd never taken a good look at me. She never once said "I love you".
The really odd and mystifying part of this is that they were really fairly pleasant people who always had the best of intentions; they were simply complete failures at raising children. It seemed they didn't have the first clue how to do it, and didn't try. I grew up feeling more like livestock than family.
When I got a scholarship to college I ran as fast as I could and didn't look back. I talked with my mom on the phone regularly and showed up at the house for Christmas every year, for the sake of being a good son. When they passed away I neither grieved nor rejoiced; I felt nothing.