Facebook question?? Please Help?

[OSITO]

Someone keeps spying on me on whatever I put on facebook & that person even admitted it to me. I tried blocking that person's facebook, but then that person went to his/her privacy settings & found out that I had blocked him/her when he/she clicked on the privacy settings & clicked on the blocking section & saw that I had blocked him on the "block users" section. So then that person unblocked me & continues spying on me as he keeps saying that 2 me & also told me all those stpes on what he he did to unblock me. So I know his e-mail thingy that people use to get on facebook with before the password & I typed it into my facebook page on the block users section but he/she says that they can still view my page. So my question is, how do I block someone without having the option to unblock that person & if I block that person, will the person be able to see that I have blocked him? Because he/she found out by going to his privacy settings. So is there a way & how & how do I make it possible so that that person wont find out that I have blocked him/her for good?