Your situation is happening to me too right now. I remind myself that this horrible job doesn't define me. I am not my job.
Obviously, you want a better paying job, but until that comes along think of this one as "keeping you in the game." Because without it, you just spin out, become disorganised, and worst of all, antisocial.
Philosophically for me, I hate that we live in a world where we have to have a job/career in order to "belong" to society. But that's the game and everyone's playing it. So unless you want to truly go insane, I recommend putting yourself out there. Even if it's among people not in your preferred career field. You'll be surprised how interesting your fellow employees are even at your 10 dollar job are.
I didn't work for a year and I became so isolated. I got depressed to the point of paralysis and then made myself take a job pouring coffee. I made $8.50/hr + tips. This despite making six figures at my previous job. Yep.
So keep doing your physical job and think of it as a work out--don't forget to stretch! And keep doing your stressful job--and don't forget to breathe!
And just give yourself over to the job for the time being. I don't mean give in to the crappy job, but truly be present at the job and give yourself to helping customers. Look them in the eye, listen to them, help them. All those little micro connections add up to boosting your self-esteem, and reminding yourself that you're human, and that we're all in the same boat.
Remember, your job doesn't define you. Check your ego at the door and don't complain. You may want to shout "I'm better than this!" but unfortunately you don't get to. That's what we're here for, right?
By the way, whether you're engineering software or improving homes, I doubt those are the coolest things about you. I'll say it one more time: your job doesn't define you. You sound like an interesting person. Don't die yet.