Nope, it's not selfish, doing what you love, what made your heart warm is not selfish. And also if it makes your heart at peace, than it's your true happiness. But I have some advices, maybe you can do your hobby, not everyday. Like Monday, Wednesday, Friday nights you have your hobby. Sunday time with your wife. And another days, you can help with house, etc. And also it's really good that you have people that supports your hobby. I for example don't have any, I have two of them. First one is taking photos and second one is sometimes putting tattoo on my skin for memories, that photos can't show. But my family think that making tattoo is amoral and they just can't understand why I want to do it.
