Odd problem: broken power menu / can't access login screen

I first installed Zorin a couple months ago. From the get-go, there seemed to be a couple things off about my installation: there wasn't any GUI wifi menu, and the power menu button took me to the login screen. I learned to use the Ubuntu network command line interface, and tolerated the latter issue. But now, power button problem has gotten worse. I was messing around, trying to fix my over-full OS disk by remounting /var onto a larger disk, and at some point the power menu button changed its behavior: now it seems like it logs me out and then instantly logs me back in. The 'lock' button next to it doesn't respond at all. Hitting ctrl-alt-delete also causes a log-out/log-in. Hitting the physical power button does seem to work as intended, as to the terminal commands 'reboot' and 'poweroff'. There aren't any issues on startup. I do have the system set to log me in automatically on startup.

I haven't noticed any other problems since tampering with the /var directory, which seems to have been successful.

Any help is appreciated. I'm a novice, so go easy on the jargon, please!

If you have the system set to auto login, that may be the issue. Have you tried disabling this setting and logging out? I understand the "want" to have this enabled. Does it also happen if you hit the keyboard shortcut to lock the computer (super [win key] + L)? It shouldn't, but it is possible.

You can clear out some of those logs in var. If you install stacer it can help clean up things you don't need. You can also set logs to reuse the file and only keep so much, in the form of setting a max size... though i thought this was the default.

Are you installing software to /var? Hosting websites? If no to both of them, /var shouldn't get that large that fast.

Thanks for all the tips, but I ended up breaking the OS while trying to move my /usr folder. I just did a reinstall.