When everything is falling apart - how do I answer the "how is everything" or "what's new" questions?

when your life is in shambles...and you go out and someone socially asks you how you've been and what's new -- what do you say? Everything is falling apart in my life. It's so bad that I am thinking I will have to move back in with my parents at 35. I am sadly single, will lose my job soon, and I have wrist injuries which keep me from doing well at work or having normal hobbies. I am envious of everyone around me and feel quite miserable 90% of the time. What can i say in social situations when I get asked those questions? I end up not saying anything because it's all negative...but then I'm not interacting and I may as well be a hermit -- alone in my cave. Any suggestions? Thanks...