I think that's one of the unfortunate issues we WS's are faced with. If our BS feels the need for space, then we really need to accept that and all the consequences that go along with cheating.
My best advice to you is to continue to help her work through her pain, be there for her and show her you're willing to go through thick and thin to make things right again.
It's good to have you with us "Don't give up, the beginning is always the hardest." My Mom:)
"I'm happily indifferent to the ones who have consistently been wrong" ~kd lang~