I need advice I feel like my boyfriend has a issue with my weight I feel judged

My boyfriend who I've been with 4 years thinks I need to loose Weight.

I am 23 and a size 12 weigh 11 stone..

He admitted to me I'm over weight a couple times and that he would prefer if I loose weight. He also said I have put on weight since knowing him so he's worried how much weight I'll put on.. And he said he's worried how much weight I'll put on when I get pregrant.. He likes slim girls.. He is skinny himself.. He makes me feel huge..

He's mentioned my weight a few times or when I eat things he might comment on how much I am eating or that I need to eat healthier or judge me for drinking Fizzy pop... When he says these comments I get upset and he says hes only trying to push and motivate me to loose weight because I'm always telling him I think I'm fat.. However him telling me I'm over weight and chubby makes me feel awful because I know he judges fat people and thinks it's discuisting..

He also said he doesn't want me to get like my mum..

Hes mentioned before about my stretch marks saying only fat people get them and celluite.. Sometimes he will be like to me 'stick your belly in*

Honesty all these comments get too me then he moans why I don't always want sex with him..

Aside this I do know he loves me he never wants to loose me and always telling me I'm beautiful and he's always turned on around me...

Just then he admits he wants to change me for me to loose weight.. That he's worried he will go off me in the future if I gain even more weight...

Honedtly what's everyone's advice on this..

I also wore a dress the other day I liked and he told me it makes me look really big..