Boyfriend threaten to leave me if I got plastic surgery. What should I do?

I've always felt self conscious about my body and the way I look and fhat has affected the relationship between us. Whenever a hot girl with big breasts and nice body I get self conscious and assume he's looking at her. I wouldn't consider myself ugly but I definitely don't look like those hot blonde porn stars that every boy fantizes about. I told my boyfriend I wanted breast implants and he threaten to leave me if I got that because then it means that he didn't do his job to make me feel beautiful and that I need a surgery to make me feel good about myself instead of him. But it isn't his fault I know he thinks I'm beautiful but there's so much someone can do for you. I'm doing This for myself so I won't be paranoid all the time and feel good about myself