Insecurities are stopping me!

I love this guy but feel too adequate to be with him especially intimately. I've seen his ex and she was slim and pretty which makes it even worse! I get attention and told i'm gorgeous though i don't feel it so don't really believe it. Trouble is i have such strong feelings for him that can't forget him yet the fear/ insecurities are just as strong so feel stuck. He's still in touch with her as they're friends and he has told me he has feelings for her still but they will never be more than friends again. This makes it harder still to make me feel good enough.
How do i get over this??

Meant inadequate sorry!

ive got the exact same problem tbh. you just need to think that that girl is his EX, and notice your own good qualities.

Trouble is he's done/ said things to show she still means more to him :'(

Then he's not ready to be with you. You know the answer right there. Nothing to do with her looks. She can be a dog and you would still feel the same because he's not ready for you.