Recently the award winning preacher (and my lovely wife), preached about how it is that it is only when one feels loved that one can then love another person. Her example was the Beauty and the Beast story in which the Beast was only able to love the Beauty when the Beauty showed loved toward him.
While you can listen to the entire sermon here, and I hope you do, the overarching point was that it is only when one feels loved that one can love another. An abused child will have a difficult time sharing love to others since that child had not experienced love themselves. This is what the power behind the message that "we love because God first loved us." We are able to love the enemy because we have felt loved. We can only trust when we have felt trusted.
When we were in seminary there was the pastoral care line that says, "hurt people, hurt people". That has proven itself to be true to me. Those who are abused tend to become abusers. Those who are wounded tend to act in a way that wound others. To build on that, "trusted people, trust people" and "loved people, love people" and "forgiven people, forgive people". This is the Good News of God in Christ. You are trusted, you are loved you are forgiven which then gives you the ability to trust, love and forgive others.