Then why did they tell me I was?
OP, I'm going to answer in good faith that you are genuine.
Because they were neanderthal abusers intent on keeping women in their place by ensuring that 'women's work' stays in the sphere of women, whether consciously or unconsciously.
I'm horribly sorry that happened to you, it's awful, and I'm unsurprised it left scars. Feminists fight against that kind of thing. Feminists fight against the idea that there are girl things and boy things. That there is a right way to feel like a woman and be a woman, and a right way to feel like a man and be a man.
So when people say that a boy liking pink and dolls is a 'girl' thing and indicates that boy is closer to being 'a girl' than other boys, it undermines what we've been working so hard to change. It sets us back and tries to box us back into the historical position of social and economic inferiority and weakness that we have spent the last century trying to dismantle and escape. Gender stereotypes are damaging and yes, they do hurt us. As you have learned so horribly, they also hurt men and boys.
My younger son spent half of yesterday pushing a dollie in the pink pram we picked up for a pound at the charity shop. Then my husband took him for a walk in his pushchair. My husband is no less 'feminine' for taking part in childcare activities than my son is for imitating that behaviour in his play, as children do naturally as part of learning and developing.
Those who suggest that dolls and prams are only for girls are also implying that babies are the work of women. And that's not ok.