Spoilers:

Is Alan Wake a character created by Tom Zane, i know that Alice divorced him and did not drown. who was the old woman?

As I understand it Wake was created by Zane and the old woman was the manifestation of the dark presence in the lake. Outside of that a bunch of other stuff can be worked out about the game, and OXM have done a pretty good interpretation of it here (major spoilers of course), but the DLCs still seem to have left everything on a bit of an unfinished cliffhanger. I really liked the main game but I've felt like the DLCs have dithered around story-wise, offering some interesting setpieces but bringing little interesting or conclusive points in the way of story. They feel somewhat tacked on.