Trust is the basic foundation for a relationship.  There is no meaning in the relationship without it.  Even good communication wouldn’t help you get anywhere if there is not trust.  When this fragile concept is broken, your partner will never hear anything you say, until it is repaired again.  One should try to realize how trust gets broken between him and his partner before he tries to repair it.  Trust is usually destroyed in two ways: You break a promise you made to her, and the second one is when you hurt your partner in various ways.

When trust is broken because of broken promises, it is the duty of the one who broke it to build it back up.  If you break a promise, take responsibility without hesitation for what you did.  Only if you take the courage to admit that you have erred will your partner let you explain.  After you have taken responsibility, offer your partner a sincere and heartfelt apology.  Don’t let your ego prevent you from apologizing, because people really want to hear that when they are hurt. 
Ask your partner if there is anything that you can do to make her feel better.  This helps prove that you care for your partner and that you are willing to do anything to make her feel better.  When she responds, listen carefully and do what you have to so that she feels okay.

Next is the step to create a new agreement between the two of you and commit to one another with complete confidence. When you offer to make a promise not to break the trust ever again, it gives your partner hope and makes her feel that you are sincerely sorry for what happened.

Always thrive on keeping your trust intact.  Once its broken, it’s hard to rebuild.