I don't have many IRL friends but told a few online friends just slowly nonchalantly and they were very accepting and understanding of it. Now, in addition to that, I told my family about it 2 and a half months ago around the time I started fully accepting my ABDL side and buying the good ABDL diapers. I had gotten really obsessed and insomniatic over the ABDL stuff after only fantasizing about it for over 21 years. I never once bought a diaper until recently, and I regret that now since I should've embraced this more years ago and I may have been happier in the long run.
I got to chatting with some people, one of them recommended I tell a parent. I thought "Heck no!" at first, but then I days later started considering it. I read a book called "You're Not Broken: A Guide to Self Acceptance for AB/DLs" by Dr. Rhoda and it brought me to tears but also helped me understand so much about why I am how I am. It also mentioned how it's a harmless vice and isn't something that can just go away. You can suppress it but it'll always come back. Almost like sexuality perse.
Eventually, a few days later, I decided I would tell my Mom (I live with my parents too) once they got back home from vacation on that coming Sunday. But 2 days later and more insomnia and I decided instead to tell my Dad first while they were still on vacation because I trusted him, and so I did a call on Thursday instead and told him everything. I said I like diapers, I'm what's called ABDL (adult baby diaper lover), and it's something that makes me comfortable and relaxed and it's something that's been a part of who I am for many years and I've always lived in shame and fear over it. It's not something you can 'cure', it'll always be a part of me one way or another. I like adult diapers and baby diapers. My goal is to be able to buy and wear in the house.
He then asked if he could loop in my Mom which I obliged, told her the same thing, she asked a few more questions and they were both very accepting and said they just wanted me to be happy and were sorry I felt so down for so long. It wasn't the weirdest thing they had heard of and they had no issues with me doing what I wanted with it. Within about 2 weeks of that, I was fully 24/7 as I am now. I've since told them about my AB/Little side, that I have a pacifier, showed plushies, mentioned ABDL friends, told my Mom about my long distance Daddy, and even showed my Mom some of my diaper designs. Both of them encourage me to go out and meet other ABDLs and go to events, etc.
Beyond that, though, no further participation. They know I wear 24/7 and don't use the toilet. We joke about ABDL stuff a lot. I also came out as Bisexual to them in early March and fully accepting as well.
Now, my situation may seem great but I'm sure there are people out there with even more accepting family/friends (that like to participate further), but that can be unhealthy and I never expected them to do that. But at least I can be myself and not have to hide it from the people I care about the most and whom I live with regardless if I was living in their home or if I visited every now and then. The cat's out the bag and it feels good!