Been with my gf for 5 years now and we live together. Never tried to limit my time in front of the computer, can sit in the living room with my laptop all day some days. I have always been honest about the computer being my "thing" and what I like to do when i have free time on my hands. There is rarely a day i don't spend at least several hours in front of it. Luckily she accepts that part of me, and is cool enough to never put me in a position where i have to choose between her and what i like to do. In return she gets to do what she likes to do, and when i am not at my laptop she has my full and undivided attention and gets treated like a princess.
She has not a single game installed on her laptop. At one point she had "The Sims" but she thought it was too time consuming so she UN-installed it again. We are very different in that sense as i play wow, sc2, diablo3, read forums, follow several series on youtube, and from time to time have anime-marathons 12 hours straight.
What I'm trying to say is, if your are honest about who you are, and you present it with a gentle "take it or leave it" attitude, and you otherwise treat her good, then she won't have a reason to wish to change you. You just have to outweigh the negative sides of your life with the good (none of us are perfect, so she shouldn't expect you to be either). Like when i am done with this post i am going to walk in the middle of the night out of town, and pick her up from a 25'th birthday party she is attending, because she doesn't like to walk home alone when it's dark, but is also too cheap to buy a cab home lol :P you just have to make up for your faults in other aspects.