The most embarrassing event would have to be when my parents first caught me wearing a diaper. It wasn't just a diaper either, it was a wet and soiled diaper at that. I was 14 at the time, so that was a very uncomfortable discussion to have with them.
I got caught because my parents had to get the family laptop that I had been using earlier for homework. It was late enough in the evening that I thought it was "safe" to wear and mess my diaper for fun, with the intention that once it was late enough, I would sneak outside to throw the soiled diaper away in the trash. I thought I had the door locked, but evidently it was not latched, so when my mom came to my room and knocked on the door, it opened a little bit, and then she poked her head in to talk to me.
Since I thought the door was locked, I wasn't wearing anything apart from the diaper. Since there was no time between her knocking and her entering the room, I had literally zero time to cover up. Instead, I was sitting at my desk in just a diaper, with a poop bulge in the back and an obvious pee yellowing in the front. I jumped up because I was startled by her being in the room, and tried to cover the diaper with my hands, but that was pointless because she had already seen. She made my clean up in the bathroom and I had to do a "walk of shame" to the garbage with them watching.
What followed was multiple hours of uncomfortable questioning from my parents. Things like "is someone making you do this?", "why are you doing this?", "are you hurting yourself?", "are you doing this to hurt us?", "did we do something wrong as parents?", "will you go to therapy?" and so on. Then it mellowed to things like "how long have you been doing this", "where did the diapers come from", and so on. Overall, it was probably the most uncomfortable thing that I had to deal with while I lived with my parents. They made me dig up my remaining diapers from the back of the closet and throw them away.
Since they "knew," I would get more and more brazen with my diapers, eventually getting to where I would wear the diapers outside of my room and around the house, sometimes wearing them in public. I got caught a few more times, but since it wasn't a "new" thing, the conversations that followed were much shorter. It eventually got to a point where when I got caught, they decided they had been unsuccessful in making me stop thus far, and more of less stopped trying to make me give up diapers.
By the time that I was 16, I started wearing diapers day and night 100% of the time. I would wear around them and they stopped making an issue out of it. They knew I still wore diapers because they commented at times when they saw them. Like when they had me help them clean out under the deck, I had to crawl under to pull out the junk store under the deck. My shirt rose up and my pants were low enough that my diaper was exposed, but by this time, they basically said "I see you are still into diapers."
Nowadays, I have a good job and am generally a responsible person, so they just write it off as "he turned out alright" and ignore the diapers.