What you guys are describing sounds like anhedonia, an inability to find enjoyment in anything. I've gone through periods like this myself.
With the lack of interest in games and stuff, it's like the other person said, people change over time. Maybe what interested you back then simply doesn't hold any interest any more.
What I've found helpful is exercise (I get to the gym most days), finding the right medication, and doing something you truly enjoy, that makes you "forget yourself", gives you a buzz and makes you feel good.
That last one is difficult if nothing springs to mind, I know. I find it hard being open to trying new stuff. I'm lucky in that I've had an ongoing interest that "does it" for me.