If you are letting your attachments to old ideas, feelings, and events hold you back, then it's time to release them in order to move forward.
Releasing is an intentional act, though in many ways quite mysterious. Whether we call it releasing, forgiving, letting go, yielding, surrendering or abandoning, we each have had experiences of something suddenly shifting and casting us into freedom. However, most of us are hard pressed to explain how we forgive and thus how we are freed. Some would say it is not an act of the will, but something that comes to us or falls upon us. Despite the mystery, there are any number of practices which can facilitate letting go. Sometimes the process of forgiving and releasing will lead us to a moment of clarity where we see the nature of our attachment and it simply falls away. At other times we may have to use any number of practical approaches like journaling, a list of pros and cons, or diagnostic tools. Some of us will need prayer or affirmation work. In some cases we'll need support from counselors, clergy or advisors.
Twelve step recovery offers a number of tools, as do New Thought and a wide range of psychological, spiritual and philosophical disciplines. The issue with releasing is not in using the “right” approach, since that does not exist, but in working more deeply to understand and see what will be needed, then utilizing new or known approaches. Often we use experimentation to discover success from which we can then build greater awareness, skills and capability. Then releasing becomes replicable and reliable, though never static.
Do you know what's holding you back? What are the nature of your attachments? What are the means for letting go? Do you understand the value of forgiving? Is your grudge affecting you more than the person you can't forgive?