For Sophie, I imagine this piece allowed her to conceptualise and contextualise a horrible betrayal of her lover; through overtly presenting her letter to the world she is able to take strength from others and allow them to take strength from her. It demonstrates courage and through sharing promotes, in so far as I understand it, an expression of female solidarity. This could easily be to take revenge on the author, but I don't think it is.
The piece was called 'Prenez soin de vous' - or 'Take care of yourself' - this is how Sophie's lover ended the letter; whilst this could be seen as quite dismissive, quite cold given what they shared together; it for me had another duel meaning - an instruction, and an affirmation. I get the impression that the author knew Sophie very well and that through writing his letter Sophie would be inspired to respond, and through that she would 'take care' of herself. I guess if my interpretation is right, that's why Sophie named it as she did...
Following my return home I did some research on Sophie Calle; she is now in her 50's, and in a vodcast interview with Tate, discussed how she finds inspiration whenever something dramatic happens to her - and as such one of her pieces is a video of the last few moments of her mothers life - allowing you to see the moments prior to her death, her last smile, and the momentary response. Voyeuristic - definitely, but whats wrong with that?
Can we have some paragraphs in that first bit?