WC8 that was an inspirational opening post. By the sounds of your empathy and contrition I dont think happier days will be too far away for you.
My 2c worth of unsolicited advice would be:
Try and look for the good things in your life, (I'm assuming) you arent starving to death in Ethiopia, you arent quadraplegic, you arent an innocent man in prison. Things can always be worse, it is always good to step back and look for the things to feel grateful for in your life.
Do something good for someone else. For me this is one of the most sure fire ways to feel better about life and my place in it. Putting a smile on someone else's face will usually put a smile on yours.
Reconnecting with Nature is pretty good for readjusting perspectives. Go out at night and just look up at the stars, it tends to make "big problems" a whole lot smaller. Being in a forest, away from all humanity's "stuff", surrounded by Nature on all sides, breathing clean air, hearing only birds, is particularly grounding for me.
Sunlight is an extremely underrated mood elevator. Heading in to winter it is even more important to try and get some sun on your skin. Getting enough exercise also plays its part, exercising in the sun, even better.
Your brain will struggle to make all its happy chemicals if it doesnt have all the ingredients it needs to do so. Fish oils, B group vitamins, tryptophan, magnesium, trace minerals, enough water, are all essential to a happy mind. Minimising things that are counterproductive to good brain chemistry like aspartame, food additives, alcohol, allergens etc will go a long way.
As a few others have suggested meditation can be very beneficial. Learning to slow a racing stressful mind down will result in discovering there is an innate calmness and peace beneath all the chatter of everyday thoughts. Just one big deep slow breath can greatly destress the way many stressful situations are experienced.
My young niece has a great expression she uses when someone is a stressing, she just walks up and in a very cute voice says "It OK". I have seen it work wonders.
