This is my opinion, and I am going to go out on a limb here and say I am not infallible. (No!)
But here goes: The Difference between being engaged at 19 and engaged at 29---and I was both---is that the 19-year-old me would not speak up, and the 29-year-old me would have never have let that one slip.
Since I can only speak for me, let me say this: at 19, I had not yet found my voice. I knew at that precise moment that I didn't like what Julian was saying, but I was too afraid of the consequences of disagreement at that point in my life to open my mouth and talk about how I really felt.
I let things slide, but that uncomfortable feeling inside was there and it wasn't going away.