The truth is to get over an ex the best thing to do is not have contact and don't think about them. Over time you will grow apart naturally. The is nothing to do, the is nothing to work at, let them know gently that being on social media/facebook is not a good idea for this reason. I have found that the more amicable you can make the break up the better is it as the will be less thoughts running around the conflict with who you think you are. Let them know you wish them the best in life and hope they will be happy.
I did find getting laid helpful also