Most Helpful Guy
Yes, they do. It's very much possible.
Most Helpful Girl
Just because two people Breakup doesn't mean they can't and don't Makeup and that it's Goodbye, my love forever. And with an "EX" who still Marks an X in his own softie spot here, dear, there is usually motive in mind when it may come a time to Come Back... Out of the blue without giving reason.
His 'Reason' of the season may be that he is Missing the Kissing and some his and her history you both shared. He may be Not with anyone right now, and has just decided to come around as though he had just come back from town.
Go slow with his flow. If he was the One who did the 'Breaking up,' then it Is going to be hard to trust him again. You never know with Joe if he might Continue down this path of a Full circle problem pattern of doing it Once more by walking out that door.
Perhaps Friendship is really what he wants you to skip to his loo with. This is then "Friends with benefits." That is something you would then have to decide for yourself, but it won't make him jump through loops any faster.
Good luck. xx