God bless you for your honesty, anon.
Many of us are recovering, we fell for one of the many Devilish snares placed all over and below this society.
As you can see many are here to help and give advice: pray, fast on Fridays and keep yourself busy to avoid temptation and better yourself in mind, body and spirit.
As for how long it will take to remove a fetish, I'll be honest: some will be completely erased, others will linger forever in you…but you can take power away from them. As for how long it will take…it could be months, it could be years; and it's gonna be a lifelong battle full of hardships. We are so often the makers of our own crosses, to quote John Bosco.
Read some good books on the topic (Libido Dominandi comes to mind), and some of those on spiritual warfare(I read Philothea by St. Francis of Sales and I'm reading a book written by St. Leonard from Porto Maurizio) and especially the Bible.
Onwards Christian soldier!