I believe the worst kind of disappointment is in ourselves. It is potentially the most debilitating kind of disappointment because it can throw you into a downward spiral that's hard to stop or recover from. Peter had sworn undying love and fidelity to Jesus. "Lord, everybody else may abandon you, but not me! I'm yours till death" (See Matthew 26:33-75). And he meant every word of it. But under the pressures surrounding the crucifixion he yields, and three times denies knowing Jesus. Later, remember Jesus' words, "Before the rooster crows, you'll deny me three times," Peter, heartbroken by his own dismal failure, "went outside and wept bitterly" (Luke 22:62 NIV).
Ever asked, "God how can you possibly use someone as messed up as me?" Peter failed to meet his own expectations and went on a downer. But Jesus wasn't shocked. He as ell aware of Peter's flaws when he called him into ministry. He also knew that his blustering, outspoken disciple had a tender heart, so He extended grace to him rather than remove him from office. When Christ gave post-resurrection orders to "tell His disciples and Peter" (Mark 16:7NIV) to meet Him in Galilee, He reaffirmed His choice of the failed disciple. The rest of Peter's story is New Testament history.
When (Not if!) you confront failure: (1) Don't add insult to injury by letting disappointment mire you in hopelessness and despair. (2) Humble yourself and repent. Confess your sin; don't excuse, rationalize or blame circumstances and people. (3) Receive God's grace and forgiveness by faith, not by feelings. Don't let Satan convince you your case is beyond grace. (4) Get whatever help you need to get back on track-sooner, not later.
BE BLESSED AND: DON'T FORGET TO SAY YOUR PRAYERS!