I've tried, but the interest level just goes waaaaay down and i eventually lose contact through a lack of interest. None of my breakups were nasty.......but you just move on i guess.
It depends on the sitution surrounding her/him getting back in ur life. If he/she is pursuing you, sex it up! Sex with an ex after time apart is usually (in my experience) unbelievable and typically much better and wilder than when you were together.