Can't Stop

So I am currently living with my sister to help pay for funds, and get me back on my feet. Started school, so I needed any help I could get. The problem is, at least in her mind, is that I stay up until the wee hours of the morning. My sister, being a single mother, working 40 minutes away from our house, and driving a car that steals $50 a day in gas, goes to sleep around 9:30, 10 o'clock and naturally finds it abnormal that I stay up until 3 or 4am.

Being a geek, gamer, and a native to the PST stuck in CST, I pretty much have to stay awake because of how connected I am to the online world. It's just a normal thing for me, if my friends are up playing games on STEAM or Starcraft II, I'm naturally going to play with them. We've been doing this for years, and it's just who I am.

My sister is annoyed that I do this, and wants me to change. I can't change instantly and just fall asleep. My body just doesn't work that way, let alone anyone else, but like I said, I don't want to tarnish our relationship over something as dumb as me staying awake. I need to find a common ground. What can I do or say besides, it's just who I am?