ANYWAYS - Merle.
Merle is a victim of the silence of a post apocalyptic world.
We don't know a lot about the life Merle and Daryl lived in the before time. We knew their father beat them. We knew they were poor. We knew Merle and Daryl felt beholden to each other because they were all that they had. Merle didn't kill any body before the zombies came. He was a drug addict, a small time criminal, probably did some time in prison or jail but for smaller crimes - theft, aggravated assault, possession. It was the only world he knew and the only chance he felt he had. Merle believed that this was the only world for him. Good things happened to other people, they didn't happen to Merle.
But we also knew that Merle read. He read the bible - not for any religious reason but because he needed something to read. I imagine that Merle actually read a lot. Woodbury had a library, he said. He read a lot of books. At first I thought this was out of character; a stupid trope thrown in by the writers to tug at our heart strings but then I realized it wasn't. The reason Merle read and read so much was the same reason he did drugs. Merle needed background noise. He needed distractions he needed noise he needed means to block out what was actually going on in his life.
And then the zombies came and with them they brought the silence.
No cars, no electricity buzzing, no generators, no planes, no radios. All of the ambient background noise that we have had our entire lives is gone. Even if you go out into the forest with no civilization of miles eventually you'll hear a plane go overhead. YOu have to seek out silence but now? Now it's everywhere.
There's a room in Minnesota that it the quietest room in the world. It's -9 decibels. People can't stay there for very long because they start to go crazy. They hallucinate. They start to hear the function of their own organs. For Merle, where background noise is not enough, the quiet of the zombie world forced him to face things he didn't want to. Face his past, face the abuse from his father, face what he felt was his brother's betrayl. This is not a world that Merle could understand.
He tried, very hard, to make the world like it used to be. So when the Governor came along Merle could understand him. Merle understood violence. Merle understood power. But Merle didn't understand sociopaths. The Governor molded Merle who wasn't a killer at heart into a killer, convinced Merle it was a natural part of his evolution but Merle knew it wasn't right. Merle could beat a person up, he could get high, he could get drunk but kill a person? For Merle, it was the only option he thought he had.
All of Merle's actions was about Merle trying to find redemption in the only way he knew how. He was unclean now, he felt he had no redemption. He was the Governor's henchman. He knew that if Rick took Michonne to the Governor that would be it for Rick, Rick would never come back from that just as Merle hadn't. So to protect the jail and to protect Rick he took Michonne. But then Michonne talked to Merle and he realized that there was something else he could do.
Was it a noble sacrafice? It's hard to say. IN the end it was tragic because he didn't kill the Governor (although he did cripple his defenses) but he also was finally able to escape the silence. He might not have been able to forgive himself, to redeem himself, and he left his brother with A LOT of unresolved emotions. When Daryl found Merle as a zombie he lost it, lost it completely but that's a post about Daryl, not Merle.
Merle, as hard as he was and as tough as he was in the end succumbed to the apocalypse after all. The zombies are not what killed him but the loss of the world he needed.