I suspect that some of Drew's accounts of what Stacy was going thru in the month leading up to her murder are actually a projection of things that were happening with Drew.
In other words, it seems more likely to me that when Drew talked about Stacy being more irritable, ready to snap at the slightest provication, short tempered with him and the kids, he was projecting; attributing his behavior to her. It was Drew who was ready to snap, not Stacy.
Likewise, I think that when Drew got emotional when talking about Stacy praying to God for her sister's recovery, and her sister's subsequent death, Stacy's sense of being betrayed by God(that was from a previous interview), he was not emotional because of the sister's death or Stacy's suffering. I think Drew may have prayed to God that Stacy wouldn't leave him, or reveal his culpability in Kathy's murder. He may even told God that he didn't want to "have to" kill her. Thus, when Stacy told him she was leaving anyway, Drew could blame it on God's failure to make her stay. I think he teared up because he felt betrayed, not for Stacy's suffering. Thinking something like, "God betrayed me so I had to kill her." I think he only gets emotional when thinking about how he feels.
A sociopath is not able to feel empathy, emotions confuse him, so he attributes his emotions by saying that this is what Stacy felt. He really has no clue and does not care how anyone feels.
Notice how he claims that his youngest children do not miss their mommy? How stupid is that! Of course they are hurting and miss her. Thank God they instinctively sense that it is not safe to experss this to Drew!
Susan
(Drooling in anticipation of frivolous lawsuits to come...bring it on baby, I LAUGH at your lawsuit!)