You only screw up your life when you don't schedule your day, like, how the fuck do people ruin their social life. I play a lot and I maintain a very good social standing, It's easy to take a portion of your day and dedicate it to work or friends.
It seems like you're blaming your lower marks on video games. The fact is, you're lazy. Games aren't stopping you from doing your work or studying during class, or at least an hour when you get home.
We'll see you in a few weeks, they all come back. You'll eventually figure out it wasn't playing, it was the fact you don't do shit.