Lavender was attacked by Greyback during the battle of Hogwarts but I don't know what became of her, was she killed? did she become a werewolf?, or did she just do the route of Bill? i don't know the answers to these questions and it drives me crazy. What are your thoughts?
From just a brief bit of looking around on the web, I've found that the movie decided to declare her deceased, according to a Harry Potter Wiki. But, no there's nothing really concrete about it in the books.
I suppose I could agree with her being dead since she was never a character I gravitated towards. But at the same time, I think it might have been interesting for her to be a werewolf. If I'm remembering her right, she could be a bit vain. It would have been an interesting challenge for her.
I do think that this is very amazing question. As movie reports the Lavander died killed by Greyback. But a few people think about her death/future in a book. For myself I think that she ended the same as in the movie; she died of Greyback's attack. I think that he had attacked her strongly and even too powerful for her managing to survive. She was killed somwhere when all of persons were fighting and probably rarely anyone took time for looking and taking care for her. There was mass of bodies and many of them were death. So my opinion is that she died fighting for Hogwarts; with honourable death.