Um... First off, you really thought she was going to create Outland? Kroak pretty much did that for some Lizardmen, that's where the rumors came from.
At the end of Khaine, she opened a dimension to a pocket realm where her daughter went, with Araloth watching over their daughter, and that girl was supposed to be the key to creating life on a remade world. Lileath, of course, would just die with this world. *That* was the plan with her, not Outland. But it does sound like they took even that bit of hope and threw it out the window. (Or perhaps just forgot it, which would be unforgivable.)