I'm really embarrassed to admit this, but... I can't braid behind my head -- too uncoordinated. I have to be looking at my hair in order to braid it. Plus, if I put it into one braid, it would be so thick and heavy it would give me headaches, and beat me to death from behind -- my plain-old ponytails are more than 2 inches thick -- but a ponytail is how I usually wear it, because it's just easier, and I'm not vain enough to worry about how I look, when I'm not going anywhere but the mailbox.
I used to braid it into 2, at the sides, for the wavy effect it gives, after you take out the braids (my hair is naturally wavy anyway), but I got tired of that; now I use the flat-iron to get rid of the waviness and fuzziness, and that helps a lot too to reduce its thick texture -- it seems more like a normal head of hair than a double head of hair. But, I have to do it in layers, there's just so much of it, and it takes FOREVER, so I'm really starting to think more and more fondly of a very short cut, and wigs. Guess I'll need to wait for the hot flashes to finally go away, or a wig would be much too hot.
Andria
Apparently braiding behind your head is not a normal skill. So, you're not alone. But, I had no choice.
When my son was a baby, he was allergic to disposable diapers. (Disposables were still in their infancy and not many choices back then.) So, I had to rinse out cloth diapers with hair down to my knees. I learned very quickly to braid my own hair. Which I would then stuff down the back of my shirt. It became such a habit that I still frequently find that I've braided my hair without even realizing that I've done it.
The headaches is why I finally cut it. But, my hair wasn't as thick as yours. I only got headaches when my hair was wet. But, that was enough.
Have you tried having your hair cut in layers or whatever they do to thin it out?
By far the best way I've found to tame that unfortunate tendency is to have it all the same length; currently a pageboy "bob" that has grown out to just past my shoulders, which means I'm just past thinking of getting it cut again -- my arms seem to be too short to deal with the back of it! 
