She won't be in MKX. She probably ain't coming back.
I don't believe that at all. She's a fairly popular character that NRS clearly likes. She isn't getting killed in the comic and was highly requested as a DLC character for MK2011. She might not be in this game, but we have no idea what NRS is planning on doing with her. If she is DLC, I can see her being in MK11.
Problem is with the route NRS decided to take with MKX. Although we assumed the focus would be primarily on the netherrealm war (which I don't doubt Tanya would then have a big role in the game) it's now on the newer generation. Tanya isn't needed to trick Liu Kang, and Edenia doesn't have any focus because both Kitana and Sindel are dead (although this might be the case after MKX).