The statistics say that one in four people has some kind of mental illness. I have a feeling that if you just include writers in the equation, the figure would be a lot higher than that.
It's not too surprising, really, if you think about it. What other profession has your emotions riding high and low more often than a roller coaster? Actors, artists and musicians ride the same roller coaster, but it's unique to the more creative vocations.
When a WIP is going well, I am jubilant. This is the best thing I've ever written. I finish it off, send it out for critique, and it gets soundly ripped to shreds. Then all of a sudden it becomes a piece of crap, and how could I ever have thought what I was writing was any good? If it's had a particularly harsh flaying, I might go crawling into a corner thinking I'm a completely rubbish writer and I should stop pretending I'm a writer and focus on the day job instead.
However, maybe I get through all that, and eventually the book gets accepted somewhere. Celebrations ensue. But then after it gets published, the royalty statements arrive and it's not selling. Or there aren't any reviews. Since a lot of online reviewers will only publish favourable reviews, not getting reviews is amost as bad as getting an unfavourable review - since I then start to assume no reviews means everyone hates the book. And I'm depressed again.
Then suddenly something appears online, out of the blue, from someone saying how much they enjoyed reading my work, and I'm riding high once more.
Sometimes I feel I'm on the brink of something really exciting. Life-changing exciting. Other times I feel as a writer I'm making barely a ripple in an enormous pond, and really no one will notice or care if I remove myself completely.
Even the most well-balanced person can't help but be affected by all these constant ups and downs. No wonder so many writers feel like they're going a bit mad.
But. Here's the thing. We're all on the same roller coaster. Every single writer I know, without exception, from the beginner writer to the one with several best-selling novels under their belt, goes through the same ups and downs.
All you can do when the ride gets rough is hold on tight and wait for the calmer bit to come along. Because it invariably will, and when it does, you are reminded why it's all worth it.