Struggling with Body Dysmorphia in a New Relationship

i’ve been in recovery for my anorexia for 3 years almost, and i’ve been in CBT for my depression that runs alongside it. the problem is, i began a relationship this time last year - so we’ve been dating over a month. however, he doesn’t seem to understand my body dysmorphia or why i struggle to eat, and why i’m so incredibly insecure about myself. we love each other a lot, and i know he tries his best to understand, but i need advice on how to see myself in a better light in more intimate situations so i can enjoy it and not worry about it so much. alongside it, i also want to stop comparing myself to his past girlfriends/ crushes to the point where it almost eats me up inside.