My girlfriend 23F said she finds my best friend more attractive than me 24M

My girlfriend (23F) and I (24M) have been dating over a year now and we were friends for a year before we started dating. 2 days ago I was talking with her about my best friend and a girl he met in a hostel. My best friend asked her out but the girl rejected him. We were on a video call and my girlfriend jokingly said ''It's surprising because your friend looks better than… this(me)…and he is single.'' while she was pointing at me with her hands. I was shocked and left the video call. She texted me a couple of times saying ''it was a stupid joke'' but I can't and don't want to talk to her again. I feel horrible. I reacted this way because this happened a few more times in the past. I showed her some pictures of my best friend and I and she always commented how he looks attractive (jokingly) and she sometimes asks me if he's coming to our city. But the thing she told me 2 days ago was the last straw. I'm not the most attractive guy but I'm not unattractive as well. I'm just an average guy 5'10 and 150 lbs. She always tells me I need to hit the gym and I am unable to do so because of my current job. She rarely gives me compliments maybe 4-5 times in total since we started dating. I really don't know if I'm overreacting I honestly don't feel like I want to talk to her again because it feels like whenever I see her or my best friend I'll always remember her finding him more attractive than me. She says it's a joke but I think every joke has a truth to itself. What do you think and recommend?