[General Battuta]

Exactly.

In fact, I believe they hinted in an interview that she decided to kill herself as early as the scene where they were flying back to Galactica in the Raptor.

[iamzack]

"Don't freak out, don't freak out"?  Meh. Probably more like once she had calmed down from that than while she was panicking.

[Deckard]

From my point of view Dee killed her self because she losted her husband, the huge deception Earth represented for them all and finally because she thought was possible to recover his husband. In the moment she understood that that would not be possible she took the fatal decisition.. Hearth-breaking, indeed..