My girlfriend is really close with her siblings and every second week of the month she always has all of them over to have dinner at our apartment so they can get together. It’s a large group of 5 other siblings so it gets loud but it’s all fun and they’re very nice people and we all get along. Her brother is really cool and builds computers for fun and I think that takes a level of knowledge that I don’t really posses so I’m like very happy for people who do things like that and I do see building computer is a hobby because it takes skill determination and a lot of time to do and there’s a healthy component behind I think. I think I see it as a puzzle.
He got upset at me though when we were talking about some computer parts, he was saying how one computer part is running very hot that it burns the cables and breaks the computer and even though this happens he says it’s rare and he still wants one. I asked him how that happens and he said it’s usually because the parts are put under a lot of pressure when they’re being used and sometimes they get really hot and they break and he said it’s usually because of a video game. I laughed a bit and said something like “breaking a computer over an video game lol” but I don’t think he got it and he said “well that’s the whole point of the parts to play video games.”
I laughed a bit but he wasn’t laughing and looked like a said something rude. I apologized for not knowing about the computers and he said it was okay. I told him that I only play Mario kart every now and then and that it’s my favorite game because me and my gf play it every now and then and that’s when he said “that’s a good hobby for you both” and I got confused and said “it’s not a hobby just a bit of fun.” He said hobbies are supposed to be fun and that’s why games are hobbies because they take a lot of time and energy. I frankly disagree with this so I told him “people put time and effort in work but work isn’t a hobby” and he got mad again and said “you don’t know what you’re talking about.”
I think I upset him over the computer parts so I tried to make it up to him by saying “I think building computers is a hobby and that takes time and effort” but then he said “don’t patronize me I know what you’re doing” so things got really sour. He left the dinner table and went to watch tv.
After driving him home my sister told me that he spent a lot of money like thousands on online card games and that it was a sensitive topic for him. I didn’t mean to offend I really like him but now I feel like he probably thinks I’m some condescending person. Is there any way I can make it up to him?
my bad... I hope he does not have 
tendencies. If he is funding it himself then its whatever.