I think we all have some of those funky days. Right now our weather is so blah I'm just dragging around. Look at what you have instead of what you don't have. If those kitties of yours could talk they would tell you what you have...listen to their sounds of contentment and their well fed looks and you will feel rich.
Work on that new hobby/business you started, it might surprise you in a few years.
Most importantly if you have your health, you have it all. Nothing else matters, believe me.

Hoping you will shake this feeling and realize material stuff just doesn't matter.