Insanity
I fear the day that I don't come back. That I fall in and can't get out.
I fear finally losing control of my mind, of myself.
It's only a matter of time, I'm sure.
Soon enough, I will dissolve. The already weak bonds holding us all together in my head will deteriorate for good, and there will be chaos. No one personality in control, no way to put on a sane facade.
I guess it's not so much the eventual descent into permanent insanity that scares me, as I've already thought quite a bit about it. My fear is more of becoming visibly insane.
Currently it's all just in my head (or so I've been told) but I fear the day when it all comes out. I fear what I (whatever "I" even is) could and would do if I (which in this case may or may not mean something different than the "I" mentioned previously) lost control.