In my scenario, I don't have another job lined up and didn't have much opportunity to follow through on my college education with limited budget to go back to school. I have also repeatedly been passed over for promotion many times now. I also work in a unionized place and ultimately decided to take on the task of being a union steward to help develop new skills. I am also considering running for the open labour management position to also help pad the resume and to gain some more experience. Ultimately, if you can't get promoted, volunteer for a position in the company if an application isn't required. Then leave once the right opportunity comes along. I also have many grievances in the system. So i do stand to make quite a bit if money if the grievances are successful.
I would say it is best to line up your next job before leaving. And find the opportunities to learn something new or expand your skillset on your way out if there are any. I would also see about taking stress leave if at all possible as well and visit your doctor if you go down that road.
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Your Aspie score: 130 of 200
Your neurotypical (non-autistic) score: 88 of 200
You are very likely an Aspie