OCD can simply be cured by a mental excercise in just one day. Your mind is tricking you in making you believe that something bad will happen to you if you don't do the OCD ritual. You need to start believing that something bad will happen if you do any ritual at all. It works and OCD will be cured forever, because now you have a new form of OCD, the one that don't allow you to do shitty things.
Thanks for your input, if it was that simple...it would work for millions of people who have the disorder, unfortunately for some people if they were to think that something bad will happen to them, then fear would overwhelm them and make the situation worse in some cases.
It's all in your head. Make yourself believe that the worst thing you can imagine will happen if you ever to do some OCD stuff again and it will go away by itself. You will instaure a new OCD in your mind, one that will help you.