Do we have a "Why are you #$%@ing miserable today?" thread? Because I feel like that might be more appropriate for me at the moment.
Mental Health and Suicide
Long story short: YES. Stress produces hormones and toxins, and if you spend a long enough time marinating in those: your body forgets how to work properly without them. You need a vacation, an extended period that is relatively stress free. Failing that... you might need medication to help...
www.allspark.com
Good luck with whatever's happening.