My father has always had an interest in computer games and the wallet to back it up. We usually had an unspoken agreement that he'd buy the console and I'd buy any games I wanted and it'd usually balance out fine. He was particularly into Doom, Sonic the Hedgehog (Mega Drive, of course) and Tomb Raider. Tried to get him into a Ocarina of Time once but I don't think he really had the patience for it. My mother never had an desire to play them but my dad used to when he had the time for them. He certainly finished the first four Tomb Raider games by himself, at least. In fact, we used to help each other out with our games. Particularly Pilotwings 64 when he would do the hand glider levels, I'd do the jet pack ones and we'd split the gyrocopter ones between us.

For you, I agree with what Omecle said earlier. It's up to you what you want to do now and at the end of the day, your mother has to realise that you have different interests and enjoy playing computer games.