OP = neurotic.
Anyway, like you I had big dreams when I first hit the law school shores. I think most students do. I did better than you, but ITE even the traditional "top 25%" requirement is going to get you much, much less. So we're essentially in the same boat.
Life isn't so bad, though...we'll make less money, and (perhaps) we will be a bit less stressed. I'm not going to kill myself if I only end up making, say, 45k a year. Not going to happen at that salary.
Stop bringing these doom-and-gloom thunderclouds over the heads of everyone else. We're all upset about the economy and our own lack of a 4.0 GPA. That's life. Were I in the bottom half of my class, I would probably be more despondent, but my realistic options would be to stick it out, try to improve, or drop out and work at Starbuck's or something. I think most people who end up in the bottom 50% will stick around, anyway. Part of it is inertia, part of it is lack of a better option. Even at 45k a year, after taxes and after a massive monthly loan payment, you're still doing better than a lot of my 20-something friends who went to college, graduated in a recession, and only found bad jobs.