First off, I would recommend you keep your desires to yourself. Your mother knows you have them, and presumably knows you use them, and that's more than enough. She likely won't want to know more. Let's turn it around... Would you ask your mother about her sex life? Would you want to know about it? Would you want to know about her underwear? Probably not. She knows enough, and I'd leave it alone for the time being. Your mileage may vary, but for most parent/child relationships, this is not something they want to know about. They might appreciate you trusting them, and they might appreciate knowing it's not a medical condition they need to worry about, but by and large, the overriding thing is that they probably want to know as little as possible, with the exception of whether or not you're healthy.
The idea of wearing diapers for personal desire is not on most people's radar. This generally falls under the category of exposing people to kink, no matter what diapers really mean to you (to some, they may not personally consider it a "kink," but it should still be treated the same way, with regard to involving others), and...it's just one of those things that generally shouldn't be done, especially since you don't know how she'll react, and you're reliant on her for housing. She's likely assuming you have a medical condition, but telling her you're wearing them for other reasons could go very poorly. It might go well, but that's a risk I wouldn't take. Plenty of people have asked the same question before. The answer to the question of whether you should do it is almost always a resounding no. The answer to how it's turned out varies wildly.
Personally, I was stuck living with my family and lacking funds, at the time that my bladder started acting up again... I had to ask my family to get me diapers, as an adult. That was not a fun experience whatsoever, but it was handled amazingly. Just treated it like it was nothing, and they actually got a little annoyed at my tendency to hem and haw when asking to be resupplied. The sheer level of how much of a non-issue it turned out to be was a complete shock.
I was requesting them for medical purposes, though. I've long wanted to wear them out of personal desire, and had planned to do that when I was out on my own, but...that didn't happen (health problems for me, as well). I was just going to wait however long it took to be out on my own, but then my body had other ideas. Under any other circumstance, though, I would never have involved my family in any way.
The way it's been handled, though, has me deeply regretting not asking for them when I was younger and wetting the bed, plus having daytime incontinence issues. How I managed to successfully hide daily daytime accidents, I will never know (who knows, maybe I didn't hide them successfully, and my parents just never brought it up). They were usually small accidents, but...still.
I've had both practical reasons and personal reasons to want to wear diapers for much of my life. The practical need for them probably led to the personal desire for them. I honestly think my parents were silly to ever take me out of them completely. Were I in their position, I'd have left me in night diapers at least until I finished elementary school, if they still fit, and GoodNites just about indefinitely after that. Daytime Pull-Ups or GoodNites would have been a good idea until probably the start of kindergarten, and then again in my teens. I was miserable with all my accidents, but...I hadn't been particularly shy when I was really little about liking diapers. I'd discovered that I wanted to wear them before I was even finished potty training (somehow, it never occurred to me to rebel against potty training and try to get them to put me back in them; I was a good, obedient kid). I was deathly afraid my parents would figure out I still liked them, though, so I never asked for them. In hindsight, I think my mom had hinted at her openness to my wearing them. She once very audibly said "Aww..." and then looked right at me, while watching a GoodNites ad where a kid set up bedding on the floor after an accident. I even noticed it at the time, and I think I kind of got the hint, but I still couldn't bring myself to ask. My grandmother might have even hinted at it once, asking if there was anything I wanted while we were at the grocery store together, with GoodNites just a few feet to her right (though I'm not sure she was aware of them or my wetting...yet), but...I didn't dare. And then I wet one of her beds, probably that very night.
Medical need is one thing, though. Personal desire is an entirely different animal.