Because I seem to be missing the gene for alcohol appreciation, I'll leave that topic to those most suited to it. I'll delve straight into 'what I learned from my day job'. Or, in my case, two day jobs, the SQL Database Administrator gig and the acting thing.
The DBA job taught me to recognize priorities, to operate on an interrupt-driven basis and how to remain calm while putting out potentially catastrophic, if metaphorical, fires. In that series of jobs, I learned that I have a reliable, predictable pattern of response when someone challenges a decision I've made. In this case, we were talking about the ideal build out of a datacenter. Perfect world build outs are always insanely expensive. Inevitably, management tells you that you have to find a way to build a stable, secure server farm on a quarter, possibly an eighth of the budget your design called for. When that happens, I discovered I get angry and claim it can't be done. Then I go home. And my brain starts popping up 'what if' scenarios for ways to do exactly what I'd said couldn't be done.
The writerly analog: Edits. Dev edits. Critiques. Beta readers. Whoever. If you write, you're going to hear that not every single word is brilliant. You'll be told that entire sections of your work don't make sense. When that happens, you'll react. It's human. It's instinct. But once I recognized my particular response pattern from the day job, I learned something very important: Shut the F*ck Up. Listen. Take notes. Feel anything I want to feel, but keep my yap shut. Because as wrong, wrong, wrong as all the critiques are, once I get home, it's going to happen again. My traitorous brain will start in. "You know, your CPs had a really good point on this bit...you could try..." And those awful people who just didn't GET what I was trying to say? They turn out to have been 100% right. I make the changes and end up with a much better story.
The point is that if you can identify your reaction pattern and short circuit the defensive portion of it? You can make your changes - or not make your changes - but because you didn't get all defensive and whiney, you can masquerade as a professional. I can pitch a complete toddler-inspired fit on the inside without looking like more of an idiot on the outside than is completely necessary. Bonus.
Acting pounded an equally important lesson into my head that applies as much to writing as it does to acting. It's not personal. Rejection isn't a rejection of *you*. Writing and acting may be about art to you - but to the people buying your product? It's a business. It's about money. When you're work is rejected, it could be for a reason as simple as your hero reminds an editor of her ex. She can't tell you that, and it isn't something you can control, but it isn't about you. Now. This isn't to say there aren't some publishers out there who send some truly crappy rejection letters saying specifically that the writing just isn't good enough when a 'thanks, not for us' would have sufficed. Only you can decide if you want to work for so callous a business. But again - even though that sounds personal, it isn't. Or if it is, it's not personal about *you* - a rejection like that says more about the person it came from than about who it's sent to. If that makes any sense.
So what's the take away on this last bit? Just this. Rejection happens. Yes. I meant to do that, because the thoughts are synonamous. Remember that it isn't you being rejected and wait for specific, actionable information before you begin revising. Your baby isn't ugly until someone points out the cowlick or the pigeon toes. People can intimate and hint all they want, but until someone gives you a specific, resist attacking your work in reaction. By all means, whine, mope, phone a friend, eat a box of chocolate, but don't touch that manuscript until you have an agent or editor say 'I had a problem with x'. Then and only then do you have enough information to act on - and even then, I'd argue that you shouldn't operate on your manuscript without a second opinion.
Does it help? Knowing it's not personal? Or does that make this business all the more crazy-making?