treat your job like job. at quitting time go_the_f*ck_home and don't even think about work. i know it's hard to do, but this is where all the anxiety is coming from, you are bringing your work home with you.

also... another reason i've experienced that caused anxiety is financial uncertainty. if you're making "several hundred thousand a year", how much are you investing, not saving? do you have a bunch of stocks and property? or is everything spent the second you get it? putting together a financial future for yourself through investments with diminish the anxiety entirely.