All in her past - don't worry about it - made her what she is today - no problem at all ---- except.....

Except she has in her past had a pleasant experience with another lady. Mmmh - that means the single common hindrance to a FFM 3-some no longer exists for her. The thought of touching another woman holds no horrors. I would say that a little subtlety on your part could give some very interesting results. Hang on that lady, but give her the opportunity to bring something nice home for you to play with as well.