I was very scrupulous in the past. Diagnosed OCD as well. I know what you are going through.
Listen… Obedience is all you have to overcome your scrupulousity. The Church does not have a official declaration on everything that our minds (us suffering with scrupulousity) can come up with. Let me try to explain…
The Church can tell us what constitutes Mortal sin. Grave matter, Full knowledge, full consent. There are gray areas in there. Not every priest can pinpoint exactly when something crosses the line from grave matter to Mortal Sin. We have to sometimes use our best judgement. The Church, at this time, does not provide a official guideline on how to apply the three conditions so that we know for sure exactly when we cross the line into mortal sin. It simply tells us to examine our conscience. The problem is with scrupulous people is that our conscience is sometimes out of whack. We sometimes cant differentiate between what is clearly not a mortal sin and what is even though most people can. We know the moral law. Sometimes better then most people. But we do not know how to apply it. THAT is the problem.
All The Church has to offer us, in terms of help, is the overwhelming agreement among priests, Bishops and The Saints of old, including St Alphonsus Ligouri who suffered greatly with scrupulosity, and various other theologians and teachers in The Church is this… The ONLY cure to scrupulosity and path to peace is OBEDIENCE to a spiritual director and confessor. That is it… that is the only solid advice The Church has to offer on Scrupulosity.
Your conscience is out of whack, much like a compass that cannot find true north. Imagine a pilot flying through fog but his navigation gear suddenly stops working. He must call in and have someone else guide him. He flys through the fog blindly relying on someone who’s navigation equipment works. It is the same with us. We must allow someone else to guide us because our compass does not work right some of the times.
You will never get rid of doubts 100%. There will ALWAYS be doubts. Even non scrupulous people deal with doubts. It is part of the human condition. So we trust in God that he knows we are doing the best we can with what we have. And what The Church tells us now is that Scrupulous people need to obey a spiritual director. Complete obedience. You can only work with that. Even with doubts. THAT, is doing the best you can. How will God punish you if you are given wrong advice? You are being obedient. Your spiritual director will answer for what he tells you and I am sure that he wants to do the best he can. You must be courageous through doubts. It is the only way. If you cannot bring yourself to obey even when doubting then you will be lost in scrupulosity.
Obedience is easy. Its the courage to obey even when doubting that you must accomplish. Believe me, I have been there. I worked with a spiritual director for a year to overcome my scrupulosity. I am telling you this because I came out of it better. Scrupulosity about 95% under control.
PM me if you need any encouragement, anytime. I use to suffer just like you and I know how bad it is. I truly sympathize.