If someone defriends you on FB...

[OldLadyKnowsNothing]

...and then changes their mind, can they "refriend" you or do they have to send a "friend" request?

They will have to request you again.
HTH

send a request. Am I reading this right and, is there an actual topic for Facebook? whatever next.

they have to send a friends request. but not if they have disappeared off your friends list simply because they have deactivated their account. they will automatically reappear on your friends list if they reactivate their account. iyswim.

Thank you. :)