Are you perhaps thinking of Slither from 2006?
A malevolent, sentient extraterrestrial parasite lands inside a meteorite into the town of Wheelsy, South Carolina, where it infects wealthy resident Grant Grant, taking over his body and absorbing his mind. With the alien in control of his body, "Grant" begins to transform into a grotesque, tentacled monstrosity. He also abducts and infects a local woman, Brenda, to serve as a breeder for his alien larvae. His wife Starla becomes suspicious over the changes in his appearance and his behavior, leading to Grant attacking her. When the police arrive to rescue Starla, Grant flees.
During their search for Grant, a posse led by Police Chief Bill Pardy discovers Brenda, whose body has become inhumanly bloated from the larvae impregnated inside her. They see the floor littered with the remains of dead animals, as Brenda begs to be fed a possum, the slug-like larvae burst from her body, which infest everyone in town except Starla, Bill, Mayor Jack MacReady, and teenager Kylie Strutemyer. Those infected by the larvae become part of a hive mind controlled by Grant, who intends to consume all lifeforms until only his consciousness remains. However, Grant also retains his love for his wife and seeks to be reunited with her. The survivors deduce that killing Grant will eliminate the rest of the aliens before they are attacked by the infected townspeople. Bill and Kylie escape, but Starla and Jack are captured.
Armed with a grenade to kill the monster, Bill and Kylie head to Grant's home, where the infected are being absorbed by the increasingly-mutated Grant. Jack and others are turned into breeders for more larvae, while Grant keeps Starla uninfected in the hope of reclaiming her love. After euthanizing Jack at his own request, Bill tries to use the grenade, only for it to fall into a pool when Grant knocks it away. Grant subdues Kylie with a couch and attempts to infect Bill with his tentacles, but Bill manages to attach one of the tentacles to a propane tank. Filled with flammable gas, Grant is shot by Starla and explodes, killing the rest of the aliens in the process. With everyone else in Wheelsy dead, the three survivors head off to seek help.