Still can't login to admin area after installing "Adapt" theme

Dear wordpress community,

I’m pulling my hair out trying to log into the dashboard of my site.

This is what happened:

After installing and activating the adapt theme from wpexplorer, I was no longer able to login to my dashboard.

When I try to login, the login page reappears with empty fields, no error message.
When I try to reset my password, I get a “page not found”

Steps I’ve taken:

Tried deleting all cookies/cache
Followed most of the steps in the codex (except the url redirect) found here.

Now, not only can I not access the admin of that wordpress install, but I can’t get into any of my wordpress back-ends. All front ends are still fine.

I contact my hosting serivce and they couldn’t help (they are continuing to look into it).

Any advice?

Thanks!!