I felt really bad yesterday but I felt better when I hugged my doggie Miky.
I also want to put the stress on something I read here: I'm not a gregary, of course, but I feel good when I do things for others.
My last therapist told me "try to put a smile, even when you don't feel like, you will see as other people give you a positive feedback and you will feel better. With time, the smile will be sincere". I do it every day and it works.