My ex blocked me from facebook now he unblocked me, so is it my turn to block him now?

[wednesday]

Ok so my ex made it clear to me about 1 yr ago that he doesent want me in his life anymore and so I started off ignoring him and acted like It was fine by me but then I started to crack and realized I missed him so I started contacting him through his phone and facebook and he blocked me from all communication and it really hurt....
He unblocked me a couple of times during the year and me the dumb person I was, contacted him immediately thinking that he finally came to his senses and misses me.
Turns out he blockes me again and tells me he wants nothing to do with me.
Then why does he keep blocking and unblocking me?
If he doesent want me in his life he should not have a problem keeping me in his blocked list.
I think he just wants me to look him up again so I can see his new profile pic and see how happy he is and to iniate contact again but this time im not because I learned hes just playing games and trying to keep me under control.
So my question is,
Should I act indiffrent and not care if he blockes me or unblocks me
Or should I go ahead and block him now since he unblocked me ?
The thing is if I block him hes going to know that I noticed that he unblocked me and so I dont want him to think im all up his life trying to see what he does.
So should I act just indiffrent to him
or should I block him back?
Please help.