Was he really joking, or was his intention beyond that (long details inside, sorry)

I’ve been playing a Sim-like game with my friend. She is 16 and she is the sister of a friend of mine but she has developed a good relationship with me. She has a boyfriend, also 16, who occasionally logs in the game. I have never seen him in real life, and my only interaction with him is through the game. I met him nearly 5 months ago and my relationship with him is still pretty much the same as when we first met, because he made no attempt to get to know me. I have tried to talk to him and get to know him more as a person, but he is never interested in meaningful conversation.

The only way I get to know him is through conversations with my friend and my own observation of his behavior in the game. My friend told me that he is extremely nice to her. They would frequently chat together and occasionally buy/make stuff for each other in real life. He knows a lot about her private life and so does she. I can confirm their relationship through my observation in the game. They are almost always seen together in the game when both of them are online. He also sweets talk with her a lot and attempts to share special items with her. However, he is extremely cold to me. I am mostly invisible to him. When we do talk, his replies to me are really short, as if he just wants to get over with our talk quickly. And when he is with me but my friend isn’t there, he always asks me where she is, and logs out quickly. To other players, he mostly ignores them, even when my friends and I are interacting with them. Sometimes he approaches them and asks them again and again if they play a certain game he is playing, out of nowhere and without any context, and after they make it clear that they aren’t interested. In short, he doesn’t seem to care about anyone except for his girlfriend.

I didn’t think much of that though. I just thought it was just a shy and awkward guy, and I had no business in their relationship… until last night. I was playing together with the couples. They were standing together exchanging love talk like usual. Suddenly the boyfriend asked me if I felt “left out” (that is just a literal translation, he actually used a specific word that could either be a joke or an insult depending on context). I told him that I didn’t appreciate anyone who felt superior to me just because they had a partner, because I am the one who has the final say in my own life. I then PMed my friend asking her why he was so rude that day. My friend told me that he had no intention of hurting me. He was just joking there, and I was looking too much into it.

At first I agreed with my friend. But then I had a thought: he doesn’t know who I am and has never tried to be friendly with me up to this point, so how could he just say the thing and expect me to take it as a joke? I trust my friend because she knows his personality more than me, but at the same time… I feel like something just doesn’t add up.

So… was he really joking and unintentionally rubbing me the wrong way? And also, if someone is nice to their SO but acts insensitive and distant to everyone else, are they a good person?