Zhijn: Didnt Geralt leave Shani and the boy in TW1 because he wasnt "suited" for that kind of life. Or maybe that was just the Shani ending i got?.
Either way, she isnt in TW2.
Buxbaum: Ah well it is sad. But she did not have a large role in the books as well or? Just read the novels.
Well she's in the middle of being ploughed by Geralt when Dandelion stumbles through the window in the very first pure novel translated into English (The Blood of Elves) not the first translated 'short story compilation' book. In the book she was enamored with him like most women are, but her ehem, spirit is noticeable even outside the bedroom.
I too really expected a mention at least to the game save I imported, to at least say what happened to her. However, the ending with her pretty much sums up why there's no way it can work long term, but a little reminder & maybe a joke about the grandma flipping out that he just did it all to plough her more, or something. :P