How can I change? I'm not affectionate enough.

So, I'm one of those people that doesn't show affection much. I just can't, it's not normal, I didn't grow up with it, I don't like it, I feel it's immature.

It's causing a lot of fights and making me feel frustrated in my relationship. My SO and I have been together for a year now, he KNOWS I can't do this. He says I don't love him or that I don't try and he's the only one trying in this relationship. It makes me feel sad, like shit, and like my way of being is invalid and a problem.

I have changed for him, I try hard to be touchy to make him happy even though I just don't like it. I love him, I'm willing to do that even though he knows the way I actually am.

I let him hug me and hold my hand and kiss me even though I don't like it, at least not in public. I'm not a sweet words kind of person either.

I know it's normal for everyone but it's not for me. I just want some advice from someone who's like this or has had experience with someone like me...

I am relatively affectionate behind closed doors. I'm not like that over text or phone or in public.

How can I change? Is it wrong for me to ask for him to be understanding? What can I do about it? Do I HAVE to change? He says he does understand but he keeps bringing it up. I'm fed up, it makes me frustrated and really sad because I do love him but apparently it doesn't show enough or at all. I'm fucking crying.