Why am i so fat and ugly?

since i met my boyfriend who is 22 years older than me, i have never felt so useless. he is better than me at everything in the bedroom, he has an amazing body and he is loved by everyone. i am 19, over 16 stone, 5 ft 4, spotty, ugly and frumpy. even my boyfriend tells me to eat healthier, but what doesnt make sense is i hardly eat anything! i know he will support me in my will to lose weight, but i know for a fact my insecurities will always be there, fat or thin, ugly or not. how can i learn to love myself so that my relationship with my boyfriend doesnt end over my insecurities?