AIO my boyfriend's friend keeps speaking about my body

i'll try to keep this short because i know nobody wants to read all this but i seriously need help on this. basically, i heard from multiple friends that whilst on a night out ( my boyfriend, 3 of my girlfriends and some of my boyfriend's friends ) my ex, who i am friends with since we dated a few years ago, said to my current boyfriend because they are also friends " oh you've never grabbed ____ ( me ) tit's before huh? too bad i could do that any day ". when i was first told this i was definitely surprised and uncomfortable but i didn't want to make a scene out of it because he's just that kind of immature and childish guy. i cant control anybody's actions but my own. i got into an argument with my boyfriend today because he kept kicking and hitting me when i was telling him to stop although he knew i was already in pain ( on my period and have a tight hairstyle ). im currently home and got these texts from him. i attached the picture i sent as a streak at the end. throughout the whole conversation he just seems so indifferent and unbothered whilst i am actually spiralling. i feel so disgusting and uncomfortable right now and its genuinely killing me. am i overreacting? what do i do now?