Glutton for punishment? "Artiste?" Is there a difference?

Writing isn't always sunbeams and daisies for me. I love what I write like I would love a particularly naughty child; it can be mischievous and maybe more trouble than it's worth half the time, but it's also mine and there's nothing I can change about that.
On the downside, writing sometimes makes me lose myself. I get so caught up in the words in my head that it's like my real life shifts onto the back-burner. That sounds kind of extreme, but it's also kind of, um, true. A good example of this is the sheer number of late nights I spend staring up at my ceiling thinking of names, and where to split chapters, and how to make sure that character finds out something or other.
These sorts of 'thinking-nights' have killer hangovers, by the way.
Writing's aftermath has also made me unrealistic, lazy, touchy, cynical, angry, frustrated, devious, shallow, self-important, never satisfied - the list goes on. Sometimes I'll get in a funk for days about a story I'm not proud of or a plot that's just Not Working... Sometimes I'll carry around a complex or bad mood for months.
Is that normal and expected? Is that art with a capital A and quotation marks and italics?

Writing has also made me trusting, thoughtful, compassionate, well-versed, easily amused, engaging, meddling, whimsical, dreamy, busy... Hey, it even got me a pretty decent score on the Lit SAT subject test.

So what am I getting at? Cliche coming up here - writing changes me. Period.
And I'm pretty much okay with that.

Thoughts?