Depression is very difficult to deal with. I'm sorry you're having a hard time. It is frustrating how it can shift from day to day, and it takes a while for meds to kick in, often about two weeks. I know it is very hard to do, but when you get home try to keep your mind off things that are sad. I find that even if it doesn't seem funny, I watch comedy shows. I avoid shows full of drama or sad topics. This helps me a little, even when I just sit there blankly not laughing or smiling at all.

I know it seems impossible, but the fog will lift and you will feel better.