littleboygabe said:
This happens to a lot of us. I got discovered by my mom when I was in college. I got caught again by my wife, years later. It seems to be part of our fate. I would suggest that you first find out everything you can about infantalism first. Wikipedia covers the subject very well. Cross reference to sex mapping as I tend to lean toward that theory as to why we are attracted to diaper wearing.
Bittergray's article, "Understanding Infantalism" is very good as well. Once you understand yourself and why you are attracted to this, you can defend your position better.
When my wife discovered my diaper order, like you, I joined this site and asked for advise. The members said to be honest which I was. I waited for a quiet moment to talk, no TV etc. I talked about my past which she knew, but it was to the subject, that I was adopted at the age of two. I talked about how it was weird but harmless, and that it was something I was always attracted to. I also said that I had tried to quit it, but that it wasn't possible. I also assured her that I was still the strong person she married, that I wasn't changed in any way even though she now knew about the diapers.
Her response was, did I have enough supplies. She has supported me well in this. Parents are different, of course. You probably will have to lay low for a while. When my parents discovered my stuff, my mom made an appointment for me with a psychiatrist, and so things didn't go well at all. I tried not to wear and wet diapers, etc., but after awhile, I was back to it, but very much on the quiet. I wasn't far from graduating, and when I did, I got a job and moved out of the house. For so many, that seems to be the best and sometimes the only solution. I hope that helps to some degree. If parents don't support it, your options are limited.