My GF (24F) is a midwife and I (28M) got fat shamed by one of her coworkers.

So my GF and I were at Target on Friday when we ran into one of her coworkers for the first time. This person has seen my GF in scrubs at work but now she was wearing a t-shirt. She complimented her on her outfit and the fact that she has lost a lot of weight since we started dating. My GF said it was all because of me and I was standing right there. So the coworker assumed I was the reason she lost the weight. She then went on to say that my GF was brave to go out with me because she knew my GF wouldn’t want to end up like me. I was like what the fuck did you mean. She then went on to say that I would be a big problem for her in the future when it came to us trying to have kids. She said I might end up dying in my 40s if I didn’t change my diet. She then said “You know your girlfriend has seen plenty of women on life support who had to give birth to a baby before they died.” Let’s just say I was pissed I lost my shit and went off on her. My GF later apologized for what happened and said that this person was jealous of her.