I can not believe a man from a loving background where there is no domestic violence could hurt his partner.
My father was exactly that.
My grandparents were pretty normal parents with 3 kids. They have one son and one daughter who married/lived with partners for years with no issues. Never had any issues with their kids etc. Then there's my father...
My father used the fact he was a drinker and a drug addict to excuse why he was violent (on the occasions he felt like he wanted too), but the first time he beat someone he was 14 and he beat the crap out of a kid at school that he thought was gay. He was the school bully. Apprently he wasn't regularly violent as an adult until the drugs, but he was always sadistic.
He married my mother who was weak in terms of standing up to him, and would do anything to protect herself - numerous times she'd attack one of us to divert his attention from her. He wasn't just violent, but he was cruel and nasty. One of my earliest memories is being sat around the dinner table on a long holiday weekend watching him eat dinner and not being allowed any because of something bad we'd done. I must have been around 3 or 4 years old and I already hated school holidays because my elder brother used to steal fruit or a sandwich from school and bring it home for me.
We were taken by my grandparents when I was 7 (I was the youngest). I said something in school that made my Head Teacher call my Nana. They went to the high school and spoke to my brothers and discovered the iron burn on my brother for some supposed crime and my grandparents took us. It was a bit risky as they took us on a Friday and refused to hand us back. I remember us all cowering in my grandparents house as my father battered the door. Thankfully the court agreed with my grandparents and they were allowed to keep us.
My grandad never raised his hand to my Nana. He wasn't even a shouty man. My Nana, when I was an adult, used to despair because her father was good to her mother, and my grandad's Dad died when he was a baby and his mother never remarried - so there was no male violence for him to witness.
My eldest brother has sadly gone on to 'prove' the theory that people who witness it go on to carry it out. Right down to the fact he was angry and bullying for years, then resorted to violence when that stopped working.
I don't actually believe seeing it is what makes people violent. I think it's just that some people who are the type to always believe they are right, and who have a real sense of entitlement also have no moral compass.