When a relationship ends, sometimes getting closure and moving on can be the hardest thing in the world.
It's so difficult to get used to life without someone, especially when you've gotten so used to having them around. Often times your immediate reaction is to try to run back to the person and ask them to take you back, or you feel the urge to stick around and "fight for them", convinced that eventually they'll realize that you were right for them all along and come running back to you.
And even though "fighting for someone" always seems to work out in romcoms, grand romantic gestures and constant talking with your ex won't always end in a reunion. Sometimes it can be unhealthy to hold on to someone for too long, or to be convinced that, eventually, they HAVE to come back.
As tempting as it can be to hold on to someone, always remember that you deserve someone who is going to want to be with you, not someone that you have to convince or wait around for. If someone doesn't want to be with you, it may be time to move on and find that person who is emotionally available and who genuinely wants to be in a relationship. You deserve someone who shares in your fight.