How does one win the battle with obtrusive or obsessive thoughts which are even too difficult to talk about?
The solution will not be found in attempting to resist the thoughts. Remember, what we resist...persists. The solution can be found in a complete acceptance of what we are experiencing - just thoughts. Once we accept the reality that we have the capacity for all manner of thoughts including the unspeakable thoughts which have tormented us in this final battle leading up to this breaking point...only then can we move forward. Every thought is permissible but not every thought is beneficial...every thought is permissible but not every thought is constructive.
This happens to be a quote from the Bible (1 Cor 10:23) which has great application to the struggle which an individual dealing with compulsive sexual fantasy and behaviour may be dealing with. Our freedom costs us the price of complete acceptance. By naming our thoughts and sharing them with another most trusted individual (therapist, priest, pastor, Imam, Rabbi, or sponsor) - one is accepting ownership for the totality of the thought. Like tieing a horse to a hitching post - confession allows us to fasten our thoughts to a secure position and pursue our journey under our full steam one step at a time - the horse does not cease to exist. No longer are we attached to the horse (the obsessive thoughts), and we can exist separately from our thoughts because the thoughts are now being held captive.
Please let me know if this helps you gain some freedom.