try your best to bring him/her back until you have nothing else to say that you should have done..at least you did your best and thats the part you should stop if you did everything because we're all human beings and not robots..we all have limitations..if she/he's for you then she/he'll come back..and if not, then let go...try not to get stuck at one person...ive been there before and realized that i was wasting my time to be stuck at one person where i should have enjoy those times wasted..but here's the thing..this is part of growing and part of our life...let time heal your wounds and little by little pick yourself up..keep yourself busy and have fun.. ^_^