As a famous quote says - "You can close your eyes to the things you do not want to see, but you cannot close your heart to the things you do not want to feel."
Feelings are a very powerful tool humans have and we should always thank God for them, as they can save us from many things if we listen to them. Many times we come to the break-up of a relationship we are unable to understand why we did not anticipate it. Go back and look at how you felt at certain times in your relationship with this person, concentrate on your feelings during your relationship. Did your feelings not tell you about this outcome?