Just because you have different interests than those girls doesn't make you dull but it doesn't automatically make them bad people for not wanting to engage in a conversation about video games.

None of my close friends like playing video games. They'd much rather talk about clothes or music/movies than they would about Final Fantasy. I'm fine with that. I don't feel the need to discuss my gaming habits with them, just as I'm glad they don't feel the need to talk about Lindsey Lohan to me. I still love them, they still love me. We're all good.

So basically, either find people who have similar interests so that you can have conversations about video games or be content to have friends who don't share your interest in games.