Thank you for the comments. I appreciate others being the conversation, you always add to it.
Some people are really defensive and no matter what you do, they will defend themselves. Having said that, most people, when they feel safe, do not defend themselves. Anything you can do to help them see the situation as safe will be helpful. This comes up in counseling all the time.
One of the best ways that someone can work on defensiveness is to ask the question, "Am I really being attacked or is there some truth to what the other person is saying?"
When you are wrong, admit it and say, “I was wrong.” Ask for forgiveness, when you have done something wrong, have apologized and have done something to make sure it does not happen again and time has elapsed.
Have you noticed in your relationship that one of you struggles with apologizing? For some people, it looks as if it costs them money to apologize. It is a rarity. Perhaps, it is that they cannot fathom being wrong. Perhaps, they inaccurately see it as weakness to be wrong and to apologize (think Politicians). Perhaps, it is because when they admitted fault earlier in life, they were punished for it (very common by the way).
Back off when you are arguing. Remember that feelings are the X Factor here. You may be totally rational, have made a wonderfully logical argument and then feelings coming into play. By nature, feelings are irrational, harder to predict. Why not act as if this person with whom you are talking is a good friend that has feelings? We are often more generous with friends than with those closest to us. We would never say to them the things that we say to our loved one.
The goal of arguing is to reestablish your connection, not to hurt the other person. If you are always right when you argue, you are doing something wrong.
Change shoes (figuratively) for one day. Really try on their role and see if you would like being them. Looking at life from their perspective, how can you make the relationship even better?
Was it easier when you tried on his shoes or her shoes?