Losing your ex is hard enough on its own, yet losing your ex and then finding out that she's already sleeping with someone else is even worse.
so what can you do to stop this? And no the answer is not to go out and sleep with someone else before they do, that will only make things worse as revenge is not the way forward if you actually do want them back in your life again.
  Although at the moment you may feel like this will not happen to you, you have to trust me when I say that it probably will that is unless you do something about it.
You see at the moment your ex is in effect in a very fragile position, they are looking for a shoulder to cry on, a friend turned to and to feel the same love you gave them.
Unfortunately for you unless that person is you who gives them the shoulder to cry on, who is that friend to turn to and who gives them the love they need and miss, then before you know it someone else will be on your side of the bed.
You have to take positive action as soon as possible! But before you pick up the phone again to tell them how much you love them, and how much you want them back you need to realise that doing that just makes you sound more desperate.
Nobody wants to go out with a desperate person!