Reading these posts, my thoughts went back to what Robert Frost said about choice, "Two roads diverged in a wood, and I- I took the one less traveled by, And that has made all the difference".
It's your friend choice to make and if you respect her, you let her make up her own mind.
As a second remark, I believe S/D can be compared with "Chado", the Japanese Tea ceremony which is based on four pilars, WA KEI SEI JAKU(harmony,respect, purity and tranquility).
Chado relates to Dominance and submission and is it thereby not so that one of the most profound aspects is that the guest is responsible for as much as the host.
In order for harmony, respect, purity and tranquility to be manifest the Dominant is obligated to enter the ceremony as the equal to the one in service. It is therebysaid that the tea ceremony epitomizes the true nature of beauty, humanity, awareness of self and the people and things around them.