Beautiful Disaster by Jamie McGuire (FIC McGuire). Abby Abernathy is trying to reinvent herself as a good girl as she begins her freshman year at college, but then she meets lean, cut, and tattooed Travis Maddox who lures her back to the bad side.
The host - Stephenie Meyer. Melanie Stryder refuses to fade away. Earth has been invaded by a species that takes over the minds of human hosts while leaving their bodies intact, and most of humanity has succumbed.