Chances are that someone hacked your account as well if you had a password reset that you didn't make.
Trying to verify your friends is hard because some of them don't use their face in their profile pictures but use some other picture instead. Also some people add users that they don't know for the games and sharing gifts each day.
https://www.facebook.com/help/185747581553788
Reasons for disabling an account:
Continued prohibited behavior after receiving a warning or multiple warnings from Facebook
Unsolicited contact with others for the purpose of harassment, advertising, promoting, dating or other inappropriate conduct
Use of a fake name
Impersonation of a person or entity, or other misrepresentation of identity
Posting content that doesn't follow the Facebook Terms
Facebook doesn't even give you a warning sometimes. Chances are someone reported you for some violation.