When OCD wins it is hard to get out of the cycle it can really knock you out for a few days. OCD leaves the suffering questioning over and over again who they are, did they do something properly, is something horrible going to happen? Am I actually a monster and this is not OCD? The main reason why OCD is called the “doubting” disease is because a sufferer will never be able to satisfy it with any answer and you will be left in an endlessly struggling of arguing with yourself and carrying out compulsions. OCD is in conflict of the person true values and intentions that is why it is so debilitating and painful. It is okay when you are having a big spike to just allow the feelings and pain to exist and trying to remind yourself that this too shall pass.
Remember ERP is the gold standard of treatment, it is very difficult to ask someone who is really triggered to engage in ERP because their anxiety is already so high.
This is a really good video on how ERP works and why OCD sufferers can benefit from it: