This is a poem that my mother gave to me when I was in desperate need of it... She is unsure of the author, so I wish that I could pass on credit, but it is something so powerful and amazing I think everyone should have the chance to read it.

Love is a gift that one person makes to another. It is a gift of the heart, and the heart "signs no documents". It does not sign a lease, a mortgage, nor a bill of sale. It offers no warranties of service nor guarantee of faithfulness. It is well to remember this both that your have no inalienable right to another's continued affection and that you have no obligation of your own always to love someone you once loved.  

Sometimes, if your own life is to add up, you must subtract yourself from someone else's life. This time comes, I think, whenever you find that affection of love of someone else can only be kept at the cost of yourself. If you are on the receiving end of much criticism, if the other has nothing but dissatisfaction with you, if you have lost the sense that to be yourself is a good and decent thing, it is time to get out. If love lessens you, if an undeclared war is being carried on in it's name, if it is painful and joyless, if it is an excuse for destructive demands, it is time to let the love go and save yourself.  

You will find another love, but not an other self.