The angle your seeing them at isn’t the same as everyone else see’s.
Your b’f is just being protective, he wants you to be all his. He doesn’t want anyone oogling over you. He just loves you so much 
I’ve noticed wearing a good push up bra, plunge bra, something that gives you more oomf makes you feel a bit better.
Get a good boost bra and a tiny strappy vest top for primark, they’re £3 or something. Walk about the house and watch your boyfriends eyes follow your every move lol.
Your being too hard on yourself. I’m sure you look just great, give yourself some slack 
xx