Reasons why an ex would unblock you on Facebook?
What Guys Said 1
He got over you, his anger died down, and/or he knows you have got over him.
What Girls Said 2
His anger has died down and feels like blocking was excessive, or possibly simply necessary at the time.
He feels that he can see what you are up to without feeling jealous.
He wants to see what you are up to. Are you feeling sad? Are you happy? Are you with new guys?
He kinda wants to see you are having a bad time without him, but if you are happy, he may make an effort to reach out to you.
When you block someone on Facebook, are you able to still see what they post? Maybe he unblocked you so he could spy on your activity. Or, perhaps he suddenly remembered that he blocked you and felt that it was silly. He could have also gotten over you or knows you won't try to contact him.
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