Regarding not seeing the sun, when I was living in Chicago, I was at work and staring out the window at the continuous gray sky. I went to the fabric store. I bought a couple yards of bright sunshine yellow cotton fabric. I hung the fabric just as it was, on my office wall in front of my desk right next to the window. I spent many minutes a day just looking at my yellow wall. It actually worked for me. And was a conversation piece for everyone who walked in.
Oh, the full spectrum light bulbs I mentioned before are what they use for plants. They mimic the sun. I'm thinking that's what those light boxes are if I'm not mistaken.