How do you deal with rejection?

I'm having a bad day. As predicted the buyer of our house failed to secure finance, and when I look back at it, they effectively wasted five weeks of our time, I think in an attempt to get us to accept a lower offer at the end of this. Which we did not do, instead we've ended that contract and organised more open homes. They took a week to sign the contract, asked for 3 weeks to get finance and THEN asked for an additional week to secure finance. I was so annoyed when my husband gave them that extra week. They gave us a number last night, $12,000 less than their original offer, but I suspect that it was always going to be their best offer.

I've had a clumsy recommencement of my research and I'm feeling a little vulnerable, I haven't been rejected from anything, but I'm feeling like a reject. So I googled "how to cope with rejection in academia" and found this wonder article that I recommend you read, if you're having a bad day in the world of research.  Here's the link: http://makewritelearn.com/rejection-letter
In it a researcher writes a letter to their younger self. Here are a couple of my favourite parts:
"You don’t know this yet, but the path you’ve chosen is one of brutal, unrelenting rejection."
"You’ll question whether you belong. And even when you start succeeding, you’ll continue failing, a lot, in between each success." 
"Here’s the thing: academia is all about rejection."

One of the tips is to not take yourself too seriously

They go on to offer six tips on handling rejection. I find myself breathing a little easier.  
I've got a protocol and a database to finish. I just needed to shake this feeling off. I'm a hard worker, I love what I do and I'm passionate about finding out what will come next. I just hope that it is enough.