Hey there! I already said this in a comment but I think I should make a theory about it... so I just realized now that when it happens the attack of walkers in the teaser trailer, jane is not with them.
And Kenny just ask's for Luke, he doesn't ask's for where is Jane... this could mean 3 things:
1. she decided to leave the group or something like that, that the group knows she is not coming but she is either not dead
2. she is there, but she isn't next to them
3. she's dead
Teaser Trailer (0:51): www.youtube.com/watch?v=GeBu8oCu23Q
What do you guys think about this ?