That is hilarious, I'm sure you could have heard a pin drop in that moment. My wife still calls me by her ex's name on rare occasion... We've been married 7 years. 😅
Part of what makes it a significant other is that embarrassment is no longer a concern. Once you know you're in it for the long haul, it's about supporting one another. I've done things I don't even feel comfortable saying with the anonymity of the internet and admitted freely to them, because we're partners. My problems are their problems and their problems are mine.
My company once held a trivia and I was picked to answer a question in front of everyone. I got nervous, especially in front of my crush, and botched an Indiana Jones movie name... Probably said something stupid like "Raiders Of The Last Crusade". When I finally escaped the spotlight, he said to me "I can't believe you got that wrong" (in a friendly way). That was a huge blow because not only that I embarrassed myself in front of the whole company, he is also a cinephile and I felt like I appeared so lame.
Anyway we've been together for about 7 years now and making plans for the future.
Elbowed her in the face while having first sexy time. Some other fumbling involved and she later told me "well that was the funniest sex I ever had". It didn't bother me at all at the time but I look back on it often and think, how did that not hit harder?