Scared to have sex

My body is disgusting and i have been told by an ex boyfriend who i had sex with that im disgusting and he'd send me photos of girls diring our relationship and tell me he wishes i was like that. I have a new boyfriend and hes sleeping over at my house and he said he wants to take off my shirt but i have really bad stretch marks and a wobbly belly. It has been over a year since my ex and I'm still nervous and i do want to take my top off in front of him. Excuse the photos.