The indecisiveness you are describing is related to the OCD. If you have stopped some obsessive compulsive behaviors through medication, his one has increased as a result. I am not going to tell you how to make decisions. You are making them daily when you choose to obsess over past decisions, although these are intrusive thoughts. I hope you are talking with your physician about other medications or combinations of medicines. These sound like they need an adjustment.
I know you sound very frustrated, and I can't offer you much from this end. But, it sounds as if the compulsion is not fulfilling the obsession, which is primarily the trait of the OCD diagnosis. And this is why it does not fill completed after the decision is made.
A combination of medications and counseling may help if you work on both these treatments consistently. Please let me know if you have further questions. Gina