weight loss and intimacy issues

So I lost 40lbs two months after having twins. I didn't gain much during the pregnancy due to complications and having two infants has changed my eating habits. and stress definitely has contributed to my weight loss. while changing my clothes today I noticed my boyfriend made a face when staring at my body. I asked him what was that face for and he said that he's not used to me being skinny.

I wouldn't think much of it but he always makes jokes about my postpartum body , I want to eat fattening food he stares at me. I personally like the weight loss I do recognize I need a tone up a bit. but my boyfriend looked at my body like he was repulsed. what should I do