If you want to point out the flaws in some of the stuff he said, you could point out that some Catholics would disapprove of remarriage (unless he was a widower). Would he want someone to be as judgemental of his relationship as he is being of yours? Would he accept some family member saying that he should never mention his wife because they object to his marriage?
It may give him something to chew on. I would not expect too much though.
When I told my parents, I let them know that this was part of my life. They either accept me or not. But I am not too close to my parents, so that was easy for me.
There are probably many other approaches. One is passive aggressive where you can answer many questions with "Well, I would tell you, but it may make you feel uncomfortable." (Not sure how well this would work.)
Or you could write him a letter. That would give you time to really think through what you want to say. Then it is optional for him to respond or not.