Just playing devil's advocate: what if Erika and Charlie actually loved each other, and she cared deeply about the important work they did. She would feel obligated to carry it on even if everything inside her just wanted to disappear and forget all the pain. According to people at TPUSA it had been discussed that she would run things if something ever happened to Charlie.

As for Erika's mannerisms / behavior that people are criticizing, I honestly think we have gotten so used to seeing polished TV personalities that we forget how imperfect real humans are, especially when emotions are high.

I totally agree not everything adds up, it just isn't as clear to me which way the truth lies.