Privacy, please.

The issue of intellectual property rights is something I’ve encountered numerous times. The artist produces his or her own creative work, and gives it protection from being “stolen.” Then if someone reproduces the work, that person is rightfully sued, thanks to the law.
How I wish it were that simple. I have yet to take any class dedicated solely to copyright, so I can’t say I know all there is to know. The issue just arises in a few of my writing and media classes, where the matter is always taken in the perspective of the creator and the perpetrator. What bothers me, and constantly complicates the already complex, is this issue of originality. Because really, what IS originality? I can paint a picture of, say, a boat of sushi. How egotistical would it be to say that the work is completely mine, when, quite clearly, the focus of the picture is due to the craftsmanship of a professional sushi chef?
And to make matters even MORE complicated, let us step outside the conflict between creator-perpetrator and sandwich ourselves right in the middle: the sushi. The subject of the picture itself. Okay, let me change it up to something more animate and real, and say, someone took a picture of me.
My boyfriend’s a photographer. And naturally, most times, I end up being the subject of his work (Here's a link to one of his pictures where I become the subject). Sometimes he posts these photos on his Flickr, or Facebook, and half of those times, I tell him to take them down simply because they aren’t flattering.
And he does, bless his soul. But what if, at some random moment, as we have talked about in class, some stranger took a photo of me in all my mid-broccoli-salad glory, and publishes it on his blog? Do I have the right to sue him? Probably not, because it’s just a blog anyway. But a top-selling magazine? I’m not a celebrity, thank goodness, so that gives me some rights to privacy. But I’m interested to know where the line is drawn here.