She doesn't understand how I am capable of spending several hours at a time on a computer, but that's because her eyes aren't trained for that amount of stress. I don't think she minds that I am a gamer, in fact, there are times where we are able to play games together that she enjoys like super mario wii or mario kart.
It also comes in handy for her whenever there's a game that she enjoys the storyline of, but can't play, so she asks me to play through it for her so she can watch. Not to mention that because of my gaming abilities, whenever she has a computer or internet issue, she can come to me for help.
My sister also finds my gaming ability quite useful, my nephew is a gamer himself and she doesn't like getting games that may be too mature for him. So she often comes to me when he wants something that she doesn't know anything about. It works out both ways in this situation because I get to help her and feel smart at the same time. That and she dabbles in gaming herself and I am there to help her out of situations where she feels it's impossible.
Which is quite funny because I make it look so easy!
edit That and people seem to get a big kick out of my nerd humor, so I'm definitely living the gamers dream... Except for winning tournaments... That's on my list of things to tackle!