He couldn't open then door to his emotions again. He needed to be a tough, cold leader who could make decisions and keep the group safe, he needed to be certain that he did not allow his own weakness to cost them members of the group again.

He "closed the door" when he declared the group to no longer be a democracy and totally took over.

 

After reading Rick's statement, it sounds like he didn't want to fix his marriage with Lori until he found a safe place for her, the baby, and the group.

Rick didn't want to be distracted, didn't want to lower his guard. He was upset with Lori, but he still loved her. Once he had found a safe place, he and Lori would talk things out.

As they keep saying, "We always think there's more time."

 

Rick meant he couldn't open that part of himself that would be soft, show feelings, be of a more gentle nature. He had to be hard, shut down emotions until he found that location where Lori, the baby, of course the others too but in this 'conversation' it was more directed to Lori and the baby, would be safe. If he risked being emotional, Rick felt he risked his chances of keeping them alive, that something bad would happen. Until he found that safe place, he was harsh/hard because he felt he had to be that way to get the results he wanted which was that safe place.

Rick thought he'd find it and then he could be open again and hopefully get back to some of what they had before everything went bad. He thought there would be time, there wasn't. He didn't get to show his love again like he wanted and he lost Lori and so he broke down. Hope that helps.

 

Yeah I reckon it's this, kind of sad really...