I can’t tell for sure, of course, but you may be on to something. One way to describe OCD is that the “enough” switch in the brain malfunctions. Once a person with OCD gets focused on something, he often can’t let go. In an argument, this can look like a relentless obsession with making a point. So it could be that you are correct that this is a remaining symptom of your prior OCD.
It could also be that because of the OCD is prior years, you didn’t learn how to argue effectively. Once triggered into a defensive mode, all you know how to do is insist on your belief that you are “right” by repeating the same points, even though they are trivial. If that may be the case, a question to ask yourself is why it is that you feel “attacked”, by someone you love who only wants to solve a problem. It may be that some experience in the past makes this kind of situation feel threatening. If so, it’s important to get to the bottom of it and to identify ways to feel safe when in a confrontation.
Or it may be something else entirely. Those are the best ideas I have with the limited information.
I wish you well.