Don’t give up hope that there can be freedom from that sin that has been part of you for so long. When it is evicted from the various parts of you it’s coils seemed to reside in, you may be shocked even frightened by how huge a monster it was. You will be surprised when it is gone that you do not weigh less physically! In Christ there is a victory that can yet be manifested in you.
When you have sincerely tried some of the excellent aids and helps to freedom on offer in the Christian scene, to no avail in your case, settle in the presence of Jesus and day, “Lord this has bothered me for decades. Please take it out of me.” In your waking and sleeping hours, He will answer that simple prayer. He is looking on you with great compassion and kindness, without condemnation, assured in His own triumph.
Do you know God can do mighty things as you sleep? That simple, humble prayer for deliverance from Leviathan.. He can do it even as you sleep. You have already made your will for His Will and victory clear to Him..