ex boyfriend and facebook situation.?

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My ex and i broke up 2 years ago. He isnt the most stable of people and in the end of the day i had enough of his controlling and paranoid behaviour. I do not regret my decision and have had a much better life since him. My facebook is completely private so he can not see anything and i did not block him at the time. He has started adding me on facebook then deactivating and reactivating his facebook. Then a couple of months later he will add me again and deactivate it and reactivate it. My question is is this just a part of his controlling behaviour? i find it very odd and have since blocked him but just would like somebodys imput....its taken a while to realise he really did mess with my head and is still trying to from the side lines! thanks for your response in advance