I do not want to get letters from particular person. What can I do that?
If you open any letter in your inbox at http://www.loveawake.com/area/mail/ at the bottom of any incoming message you can see several buttons for further actions. One of them is "add to the blacklist". Click it to block any further messages from that particular sender.
You may also block any member from your chat area at http://www.loveawake.com/area/chat/, just click "Block sender" icon right behind the sender's thumbnail photo