Just finished this excellent book and worth recommending. In a similar vein to the Walking Dead and Y the Last Man but with a much darker adult tone.
Garth Ennis has pulled out all the stops to write the most twisted book of his career, Crossed! Cindy and her small band of survivors are facing impossible odds, dwindling resources, and a dearth of options. Nothing is going right, but this is no fairy tale; there are no magic cures on the horizon. When civilization crumbles in one terrifying moment; when people are gleefully breaking into unthinkable acts of violence all around you; when everyone you love has died screaming in agony - What do you do? There is no help. There is no hope. There is no escape. There are only the Crossed. Certain to be the most depraved and corrupt book of the year, this one is not for the faint of heart! Through ten heart-stopping chapters, Crossed is his horrifically visceral exploration of the pure evil that humans are truly capable of indulging. This gut-wrenching vision is brought to vivid (and more than a little disturbing) life by his partner in crime Jacen Burrows.