We lost our only source of income -our restaurant - when the economy tanked. I feel your pain. And I have bipolar disorder type 2, so dealing with stress is somewhat of a science to me, because if I don't deal with it, I can get to a point where I need hospitalization.
First, realize that worrying about anything is useless. It's a waste of time. It's like sitting in a rocking chair and expecting to go somewhere by rocking back and forth. Then, understand if you tend to be an extrovert of an introvert, so you can understand where you gain energy and where you spend it. Personally, I need a lot of time alone. I'm in the middle of a Kickstarter campaign to raise the rest of the funds we need to open a new restaurant (we've already made our goal) and with all the stress involved in planning and executing it, I needed a whole day off in bed. Last Saturday I stayed in bed ALL DAY in my pjs and only took care of my self. Daily, I remember to take my meds (not that you need them, but you might). I should exercise more, no one is perfect. I spend a lot of time alone, both by choice and by circumstance. If I don't get that alone time regularly, I'm miserable person.
It sounds like you need to be able to step away from your job and realize it's not who you are, it's only what you do. I agree with trying to find a new line of work, my husband is miserable working for others and we have been working for 6 years toward this goal of ours. And although it will be a whole new line of stressfulness to deal with, it's GOOD stress.
You might need something to help you sleep for a while. Lack of sleep can lead you down a bad emotional path and make your symptoms worse. Talk to someone, a friend or a therapist. Get your resume together and make a plan to at least look for other positions. Reevaluate where you are in your profession, do you want to change directions? Be promoted? Just work elsewhere?
Find joy in every day living. Small things like that guy who let you into traffic, or that woman whole held the door for you. Do things for other people, a kind word to a cashier, an anonymous donation to charity, find ways to be kind and helpful to others without expecting any kind of return for your efforts.
Refocus your energy to things you CAN change. Redecorate your office or bedroom. Clean out a closet. Put that anxious energy to work for you instead of keeping it all in your brain to wreak havoc.
These are a few skills I have learned to keep my anxiety over stress in check. You'll find a way. And it sounds like you might need a small vacation, are you taking those? Getting away with your husband or kids for a few days? How was your time in Erie this summer? :)