"The Walking Dead" comic books offer some serious spoilers for the TV show but it is completely opposite for Carol and Tyreese's plot.
If we go by the plot in the comic books, Carol and Tyreese were in a relationship at one point in time. Carol died in the prison when a zombie bit her. On the other hand, the Governor killed Tyreese using Michonne's katana. In the TV version, the Governor beheaded Hershel Greene in "The Walking Dead" season 4 mid-season finale episode, "Too Far Gone."
The TV version is entirely different as it has both Tyreese and Carol alive. She killed Karen who was Tyreese's girlfriend as well as David in order to protect the other members of the prison from the deadly flu. Tyreese still doesn't know that Carol is responsible for his beloved's death. "TWD" season 4 episode 9, "Indifference" saw Rick expelling Carol from the prison for good. He was upset over Carol's action and thus decided to send her away out with the zombies. Now, Tyreese is with Mika Samuels and Lizzie who were with Carol. Lizzie was the one who saved Tyreese's life during the prison war with Team Governor. She shot Alisha right on the forehead that led to her death.
Tyreese left with the kids and it is likely that we would meet him in the second half of the season.
According to a report by Wet Paint, Chad Coleman revealed that "The Walking Dead" would showcase the conflict between Carol and Tyreese. It is possible that Tyreese and the kids would meet Carol, and they would become one group. So far, Tyreese is not aware of the Karen-Carol secret. Will he berate Carol if he comes to know about Karen's death or will he let go and forgive Carol for her deeds?
"The Walking Dead" season 4 from February 9 on AMC.