I lost my characters that i played on before.

When i came back to game after some time, i lost my character that i grinded alot with.I really dont know what should i do and how can i get it back.I especially played on lordaeron and when i came back after some time, in the realm section menu it showed that there is 2 available characters to choose from but non of those are actually selectable in the character section menu.Is there anything that i can do to recover my character because i really dont want to start all over again...