"How the hell do you not get burnt out doing this?"

I really, really enjoy my job.  (When I get to do it. The three dozen things a shift that have jack and squat to do with actually caring for patients still suck my soul out.)

There's always bad shifts, even bad weeks, but when I catch myself getting overly grumpy about it, I make a mental game out of kicking its @$$.

Life really is 10% what happens to you, and 90% how you decide to feel about it. I realized it's a lot more fun going through life as the cat than as the litter box.

And when it's time for time off, GTHO and have fun. (Also, if you never go away, they never miss you. Really.) At least one county away by car is great; if it involves a plane ride somewhere else, so much the better. This year I'm picking off the 27 states I've never been to - and probably finally getting the (online, now!) BSN they swore I couldn't live without as a nurse - by 1995 (snort!). Next year, I'm either doing countries, or destinations. I want to see what a full passport looks like.

But after a week, 10-14 days tops, I start getting twitchy to get back to work. I've never not had a job (except during part of college) since I was 13.  That's mumblemumble an awfully long time, so force of habit there as much as anything else I suppose. Total days, lifetime, on any sort of state unemployment, zero. Trabajo. Period.

BTW, assuming someone does 3x12hr shifts weekly, if you pick up 1 extra shift/wk at a different facility, you network, see how other people do things, have a fallback job when your main gig craps out on you (and they will!), and you have about 20-25% after taxes of your annual pay in your hand as your Better Life slush fund if you simply put it in a jar every payday. I highly recommend it for anyone with 5+ yrs. experience. That's vacation, retirement, a down payment on a mortgage, or a new car, in return for one extra set of clean scrubs every laundry day. Times the rest of your career, that's one helluva better place to be in. Wish I'd started doing it ten years sooner.

One other thing: if you have an ounce of discipline, keep a shift log.
E.g., I'm about to embark on a 13-week contract. Or, 39 shifts. Potentially, as many as 65. Whatever.
But if you'd like to put what you do in perspective, start a little tally:
Say, something like : 4 GSWs, 19 MVCs, 42 MIs, 23 CVAs, 37 hot appys, 59 fractures, 107 psychs, 317 FDGBs, 81 peds, 126 admits, and a little boy with a toy soldier up his nose.
1423 doctor's orders implemented, 917 meds passed with no errors, 182 IVs started, 12 NG tubes, 56 foley caths, 918 phone calls, and 2 teddy bears successfully returned home with their smiling owners.
It lets you see just what an actual difference you make, and it's a metric fuckton more persuasive than the jacked up ratings on annual evaluations if you want to point out what you've actually done for your facility, if you're there long enough for an annual evaluation and raise discussion.
Trust me on that.

Like that slush fund, consider the tally another way of paying yourself first.