Just the backup and personal bind files are saved on the computer. The actual bind information is actually saved on the server in your character info. Sometimes the binds don't save correctly on the server, and only sit in the current instance of your character and are lost upon relogging or zoning.
Steps that usually fix this:
- Save your keybinds (you already did)
- Open your options and "Reset KeyBinds" (to server default)
- THEN load your personalized bind file
- Log out (to hopefully force a save)
- Have a meal, browse the forums, use a different character, or do something else to occupy your time for 20-30 minutes or so to ensure the character's status isn't still sitting in the server's "memory".
- Log the character back in and see if it worked/"sticks"
Good Luck!
Sounds valid, I'll give it a try now, then it can have all day to figure things out while I'm at work 
I'd like to see if anyone else has had a problem of this type, and possibly a solution. I have one character that has some issues with keybinds changing on their own, 2 in particular. I have my spacebar set to Target Nearest Enemy, and for some reason during play (after about 10 minutes) this changes to be Toggle Mouse Look. The two keybinds just swap places for some reason. I can set them back, and it will work for a while, then swap again.
I use the same binds on my other characters as well with no issues. I saved my keybinds to a file on a functioning character and loaded it for the one that doesn't work correctly, and the problem still occurs, only on the one character.
I don't really have any macros set up, so I don't think it's a macro-gone-bad or something like that. I do use a logitech G13 gaming pad, but I use it for all other characters with no ill effects. I've been trying to figure out what is different with this ONE character that makes it happen, but nothing is obvious to me. Any suggestions?