On the other hand, it should be noted that - for some of us - "obsessively repeating the conversation in my head, detail by detail" is why we're in therapy. My therapist might tell you that it smacks of social anxiety and that you have a streak of perfectionism to get under control. You said it yourself: obsessive.
Or it could be ADHD too, trouble keeping the mind where it's supposed to be is one problem. Plus, it can travel with OCD too, so you could have a twofer!