Disappointment has caused you to dwell on past events, so much so that it has now become a hindrance. Instead of dreaming with expectancy and anticipation for future things, your time is spent regretting and pining for the things of the past. God is calling you now to let go of those past events. Trust him to hold them and be freed to walk forward, unburdened and joyful. Accept the forgiveness that He readily offers and invite him to guide you in the adventure ahead.
But one thing I do: Forgetting what is behind and straining towards what is ahead, I press on towards the goal to win the prize for which God has called me heavenwards in Christ Jesus.