When you have a lot going on in a scene - whether it be a lot of shots, a lot of coverage, a lot of edits, or just the amount of content - it can cover up a deficit of true feeling. But when you don't have a lot of material to work with, you really have to be sincere with everything. You really have to mean it, because there's nowhere to hide.
I think all people are familiar with thinking about their death and trying to come to terms with the fact that we will, at some point, no longer exist. The loss of one's ego is very tough to reconcile with; you really have to do a lot of mental gymnastics to wrap your head around the idea of just not existing anymore.