Sorry--I'm getting a little teary here thinking about your post because I know how painful it is--
I just had to chime in here with some additional words of support from another painter. I went through the process last year and was rejected from every place (with the added bonus of 1 agonizing waitlist). The whole process really left me doubting myself and the quality of my portfolio. I, too, was really shy and intimidated by the excited posts of people who were getting good news all the time (though this board certainly helped me through the process of eliminating false hopes).
After working on my portfolio for another year and getting more recommenders, I'm going through the process again this year and was getting rejections left and right--until I finally got one acceptance, to the perfect place for me. I expect still more rejections to come.
I really think the other posters are right--admissions have only a little to do with "quality." These programs are looking for people that will make a good fit with the current direction of the program and with their faculty. And some schools (I hope this isn't sour grapes talking, but I don't think so) seem to be very much invested in what (or who) is fashionable right this minute. And we can't help it if we're not that.
So please don't question your portfolio or your decision to go through the process. Believe me--we are still EARLY in the process (unfortunately), so there are many steps to go before this year's cycle is over. And whatever happens, you are one step closer.