In all of history, only one person has overcome sin, sexual or otherwise. This person is Jesus Christ. He is the only person in history to live a sinless life (Hebrews 4:15). The Bible tells us that the wages of sin (what we earn from sin) is death (Romans 6:23). Since Jesus did not sin, He earned no death penalty and did not have to die. He chose to die anyway by taking all of our sin upon Himself, dying in our place (Romans 8:3-4; 1 Peter 2:24).
    His overcoming sin is demonstrated in His resurrection. He rose back to life and cannot die again because sin has no power of death over Him (Romans 6:9).
    All of us have sinned (Romans 3:23). All of us have earned a death penalty by our sin (Romans 6:23). No matter how hard we work, how many counselors we see, how many support groups we attend, how many good deeds we do, how much we change our behavior, our death penalty from sin remains (Isaiah 64:6; Romans 3:10-12, 19-20). Only as we accept, by faith alone, Jesus Christ's death on the cross in our place, only as we believe in His resurrection from the dead, only then can our death penalty be taken away. By faith in His death and resurrection alone for our sin, God forgives our death penalty and gives us a new life (John 1:12-13; 3:16; Romans 1:17; 10:9; Ephesians 2:8-9). We cannot overcome sin, but we can receive the gift of Jesus' death on the cross and resurrection and share in His victory over sin (Romans 7:18-19; 7:24 - 8:4). Yes, we have a great hope in overcoming sexual sin -- through faith alone in Jesus Christ alone.