Consider timing, methods and other prerequisites that need to be in place for success. Find something you can applaud and be generous in doing so. Let a roommate know you appreciate the way she completed a chore or prepared a special meal. Compliment your friend's appearance, choices, suggestions or efforts. I forgive you.
Guilt weighs heavy on the soul.
Ask forgiveness of the one you've wronged, then forgive yourself. It's quite acceptable to recognize our good points and value them. Your friend probably has lost sight of some of her fine qualities. Point out her strengths, including natural talents, interests and personal traits. Cite personality traits you find compelling, being sure to go beyond appearance.