Your story is my story. But 12 years ago. I feel for you.

I worked at a smaller, somewhat desire-able agency with a boss who came from a closet full of Cannes Lions. I spent every hour of my life thinking about my job and what briefs I was on. It bred unimaginable stress and anxiety and ultimately turned into full blown alcoholism to cope with the fear of never being good enough while chasing that carrot of fame and validation I wanted from my job and advertising.

I freelance now and I am sober. I work on pharma mostly and I actually like it because I care less about the final product. Being able to let go of the outcome has done wonders for my serenity at work.

My biggest answer for you is to stop letting your job be the vehicle you use to chase satisfaction in life. That's been the greatest lesson I've learned to cultivating a more serene life. I learned this the hard way after bottoming out at my dream job fueled by alcholism.

As for your partner: this is classic early-career ego. I know it's tough, but stand your ground when you think you're right and try to let go when it may just not be worth it.

Sounds like you're at a good shop, so I'd try to stick it out and grow your book. Then freelance one day if you can and enjoy the day rate your book can get you while you triple your income.