I echo what others have said about being afraid to blog, worrying if your stuff doesn't sell you're not validated, etc. Yes, as artists we really put ourselves out there.
When I blog, or write my profile, or even item descriptions, I struggle with not fitting the "typical artist" image I think others have (but with our diversity, that's truly an oxymoron). I'm not quirky enough, I don't like certain bands or TV shows, I don't live in NYC, or live "close to the land" on a farm off the grid (I kind of wish I did!), I don't have a bunch of cool tattoos, or hang out at the coffee place, not a vegetarian, I don't make whatever the current trend is, I don't invent fantasy stories about my work, I'm not also a writer (or bellydancer or yoga fan), etc. So I fear maybe others won't think I'm a "real" artist (though I've been an artist all my life), and they certainly won't find me or my blog very interesting. That haunts me. And it doesn't help that I don't think I've effectively reached my target market yet (assuming they're even out there), though I occasionally find a customer who really seems to connect with me and my work.
I keep believing that if I do what feels meaningful to me ("from the heart"), something I feel I was made to do, it will find it's place and I will succeed. That keeps me going! But it does require me to be vulnerable, which can be hard.