Struggling

I’m really struggling with coming to terms on ending a relationship of 3 years.. we’ve been off and on. I recently lost my mother 5 weeks ago, and it seems that him and i have been arguing more and more since then. Yes I take responsibility when it’s my fault, but he doesn’t seem to take his when it’s his. In the past when we weren’t dating he would send me pictures of him with other girls (his hand on her thigh, her sitting next to him him behind her while she’s brushing her teeth) just to piss me off..

recently he did it again as a “joke” and i put my foot down saying it’s NOT okay to be sending those types of things to the person you “like” and claim to want to have a future with. We’re both 20, I don’t want to deal with the highschool mentally. This weekend we were flirting etc etc and he said “nah nvm you definitely said this shit to the Canada boy” (ex who mentally and physically and abused me) so I said “I definitely wasn’t the one going around a bunch of girls and sending pics to the other” wnd he goes “like this?” And send a the pic where his hand is on her thigh that I’ve seen before. I starred at the picture with tears running down my face. Took a deep. Breath and unadded him. Messaged him on iMessage to delete anything regarding me and that he’s more then welcome to do that behavior in other girls chats and to stay blessed. He proceeded to say “you’re mad over that?🤣🤣 we were just joking 5 seconds before that” and proceeded to say I jump to conclusions and that it’s my fault I undadded him and that if we don’t talk after this, it would be my fault.

I struggle with extreme anxiety which results into overthinking about EVERYTHING. I don’t know if I overreacted and ruined something over a joke? I don’t know how to come to terms that what I did was okay. He hasn’t messaged me since that argument, not even an apology. I’m seriously struggling, I have nobody to talk too, I don’t have my mom to go to and cry and tell this too. I think it’s just bothering me more then it should