BF and I have been together for under a year, about 10 months, let's call him Adam. We met through my best girl friend, we will call Lauren, who was his coworker at the time. Lauren introduced us. Adam and Lauren had been working together for about a year or so when she introduced us. When she introduced us they both lived two states away from me. She has a long term boyfriend, let's say Cam, of about 4 years who she's very serious about, who was close friends to my bf as well. Adam had admitted to me that he had a crush on Lauren when they first started working together, but that he lost it when he found out she had a boyfriend, and after him and her boyfriend became friends. My BF decided after about 2 months of talking to me to move to my state and live with me. Things were wonderful.
We get along well, we have great sex, and we are in love.
We went up for the 4th of July to visit his family and to hang out with Lauren and Cam. We went out for drinks with Lauren and Cam, where we had so much fun. While Adam was drunk, he brought up to me that he used to have a crush on her. We laughed, and I jokingly said you still do. He said he does find her attractive, which threw me off a bit.
We ended up going back to the hotel, where I felt uneasy. Being drunk and wanting reassurance, I stupidly asked him if he thinks she's more attractive than me, where he admitted he thinks she is. "She has a more attractive body than you, but you have a better face." He said. He proceeded to get into an argument, where he left the hotel and took the rental car. I didn't see him until the next day, when we went over to his sisters house for fireworks. We ended up discussing it when we were sober, and he doubled down on the statement. (Keep in mind i'm 5'9, and bigger than the average woman. He's 6'3 and a bigger build.) He said that the reason her body is man attractive than mine is "because she's tiny, and she Lauren is around 5'1-5'2 and MAYBE 115 pounds. Lauren is disgusted by his comments, and her boyfriend Cam is also disgusted. She feels objectified and disrespected that he would say this to me about her.
Long story short, i've been feeling incredibly insecure since then. I can't change my height. I've struggled with anorexia in the past, and being 24 l finally came into accepting and adoring my body for what it is, and all that it's been through. I'll never be the "tiny" or "short" girl. It's made me feel incredibly insecure, especially during sex. I don't know how to get past this feeling, or how to get back to my confidence in my body. I'm not sure how to feel or if this is something i'm maybe overthinking. Any advice would be greatly appreciated. What do I do about this?
TL;DR: Bf thinks my best gf's body is more attractive than mine and i'm unsure of how to feel about it. What do I do?