Can't log in or change password

[Sarcany]

jepinto wrote:
When I log in the entire application folder opens, and EVERY application including stickies opens up.

...

Suggestions?

First get a handle on that wacky admin account.

Not clear why all of the apps are opening. Try having her log in under that account when it's safe-booted (hold down the Shift key on startup).

Then... Might as well just use your admin credential to create another admin account in the Users & Groups (Accounts) settings. Log in under that nice new admin account and troubleshoot from there.

If you can't unlock the preference panel to create a new account, that (along with the other stuff you've mentioned) tends to indicate that the sudoers file is hosed. It doesn't just get hosed on its own. It usually gets messed up only when the drive is dying or has had a major crash/glitch that corrupted the file-system. Would strongly recommend doing drive-diagnostics at that point including running the Disk Utility from the Recovery volume and if you can get it downloaded and running then do a SMART check with SMART Utility as well.