Body shamed by my ex

Ive always been so insecure about my body type especially when i was with him because he has muscles & hes in good shape & because im not curvie like other girls, i have a muffin top & i found out that my ex boyfriend called me outa shape behind my back in a disrespectful mannier. After 6 months of break up and who knows what else. Now I know i am not in shape but it honestly it hurt me & i teared up. Now i dont know what to do & i fucking hate being insecure. I lost my virginity to him & now im wishing i had a curvy body so i could show him whos better. But im just dissapointed what should i do?