"Now are we to also believe that it is Terri's wishes that her family not be with her when he accomplishes his goal of hastening her death? What is the rationale this time?"
IMHO, the rationale behind Mikey the Murderer's decision to deny her family to be with her when she died was because a) Mikey couldn't be seen not there when she died because it wouldn't look good; b) Mikey hates her family and he didn't want to be in the same room with them when she died (could anyone but a monster look at that family while killing their daughter?), and c) Mikey chose to keep them out in order to make HIMSELF feel more comfortable and look good - like in all of this mess - it's about him.
That's a pretty accurate synopsis, I'm thinking.