Due to a long spell of depression, I have spent a lot of the last couple of weeks in bed. I have noticed that my bed is no longer comfortable to be in, and it makes it difficult to sleep at night. It doesn't matter what position I'm in or what time, or anything. It just doesn't feel physically comfortable to be in my bed anymore. 

I tried changing the sheets/washing the comforter. 

I'm trying not to be in bed as much, but what else can I do to make where I sleep a comfortable place again?