6) After Rick passes out, we next see him on his horse, slowly making his way to Atlanta, down the same stretch of highway (Complete with the burnt out cars and trains on either side of him) as he did in “Days Gone Bye”, except this time, he’s also leading a parade of walkers.
7) Continuing with Rick’s hallucination, he also passes through a street very similar to the one he walked down before running into heard in that same episode, complete with the burnt husk of a bus to his right.
8) This hallucination is also where Rick has a conversation with Shane, whom we haven’t even seen (Much less heard) since Rick mistook a Woodburian for him during the attempt to rescue Glenn and Maggie in the Season Three midseason finale, “Made To Suffer”.
9) During their conversation, Rick tells Shane he’s looking for “his” family, to which Shane counters that one could argue that Rick is looking for his (i.e. Shane’s) family. This is a little reference to Rick’s lingering doubts about whether or not Judith is actually his daughter.
10) Furthermore, Shane attempts to take credit for the (relatively) violent person Rick has become, owing to the more authoritarian and ruthless streak Rick showed following Shane’s death. Of course, with this entire conversation being inside Rick’s head, this means that Rick believes he changed following Shane’s death.
11) Additionally, Rick telling Shane he didn’t want to kill him shows that, even this far removed from the incident, killing Shane still haunts Rick, though, one might suggest Shane brushing off the concern is Rick trying to forgive himself for it.
12) Finally, during their conversation on how Rick had to do thing’s Shane’s way to survive, Shane specifically mentions “How you bit that piece of shit’s throat out, and that asshole at the church with the machete” referencing Rick’s killing of Joe in the Season Four finale, “A”, and his butchering of Gareth in the third episode of Season Five, “Four Walls And A Roof”. Once again, because this is all in Rick’s head, this may actually be Rick realizing that, in order to survive, he needed to adopt more of Shane’s approach to the apocalypse.