boyfriend help

My brother and I just got into a huge fight. One of the problems was "the way I dress" he said I look like/wanna be a slut bc my shirt is too low. I said "you're not my dad I can't wear whatver I want" and all he says is "I don't like that x3 I don't want no one looking there, stop trying to be a slut" and there is no other way to get it thru his head that I hate having a dress code ! He's controlling and I want to fix that in this relationship of ours. I need advice on this, bc I always feel attacked and idk what else to say to him. The way I dress is only my concern.