There is not such think as friensdship beteween a woman and a man!
It is the nature of the man to pursue.... at every opportunity his natural instincts!!!!!
So it doesnt matter how long they have been friends, at the first opportunity that a man senses there is a chance to be erotical with the woman, he will jump at the percieved opportunity to try his luck.
Any way after being a lover to a woman i think genuine freinship could possibly take effect, if there are genuine mutual interests for both. That frienship i believe would be realy genuine and lasting for ever.
Well also talking from experience!!!!!!