Do you know what type of ADHD she has? Knowing that might change things a bit.
This is going to be really long, but I hope you find some of it useful for your situation. I don't know how your wife's ADHD presents, but I'm diagnosed with combined type ADHD, social anxiety, and depression, and I'm a woman around the same age as your wife. The things my partner does that really help me the most is to help make things easy and accessible for me.
I struggle a lot with executive dysfunction, and if I'm overwhelmed it tends to compound into paralysis. I have a lot of trouble staying organized and I'm constantly losing things, which causes me to be late a lot, and when I'm late my anxiety gets worse.
I try to think about things I do every day, and make them available to do in as few steps as possible. I like to keep items I use frequently near the area I use them in, kept together with other items needed to complete the task in little "kits" so that it doesn't take much thought to do daily stuff.
Think minimalist, uncluttered, functional areas. For example, if she drinks coffee every morning, have the mugs on a stand near the coffee maker, have the coffee already in the coffee maker so she only needs to start it, and keep any sweeteners, etc she always uses near the mugs.
Another example, going to work is particularly stressful for me, so I try to lessen the amount of decisions and prep I have to do before hand. Getting all of my clothes and things I bring to work together the night before I have to work helps me a lot, because it lessens the chances of me being late, which helps with the anxiety overall.
For me, it feels like every decision I have to make, every lost item I have to find, every time I leave the room to get something and immediately forget what I went to get, my energy is drained. So minimizing these problems makes everything so much easier.
If I'm really struggling, a messy area makes anything I have to do so much worse. If I feel like I can't do anything at all and the room is dirty and chaotic, everything is going to be so much harder. I don't know if your wife's symptoms are similar to mine, but if I'm a zombie and I can't do anything and I'm doomscrolling Lemmy too much, having my partner help me by tidying the area around me makes a big difference. I feel like I can function a bit better.
There are times when I look like I'm being lazy, but I'm not. I might look like I'm just sitting around doing nothing or scrolling or playing some dopamine-extracting game all day, but in my head I'm thinking about how I want to do everything and I'm screaming at myself to do something, but I just...can't. I don't know if she has exacutive dysfunction like I do, but when it happens to me, I appreciate that my partner doesn't make it worse by making me feel guilty about being "lazy," because it's not laziness at all.
Another thing my partner does that helps me with executive dysfunction is to just...put stuff near me. I like to paint, so if I'm stuck in "couch mode" too long, my partner will get my painting supplies and put everything I need within my reach. Eliminating steps really makes it easier to break the trance, and sometimes I'll just start painting without thinking about it.
Sometimes decision making is particularly difficult for me and it requires a lot of mental energy when I'm feeling especially bad. If this is an issue for her, I would suggest trying to make choices as simple as possible. For example, instead of saying "what do you want for dinner?" you could say "I'm feeling like Italian or Chinese food tonight, do either of those sound good to you?" I feel like my mental energy is limited, especially if I'm in a depression, and making decisions simpler helps preserve it.
You both might like the "How to ADHD" channel on YouTube. She talks about ADHD from a woman's perspective and some of her advice has been helpful for me. I sometimes show some of her videos to my partner because it helps him understand how I feel and think a bit better.
And of course, if you can, get her into counseling and/or medication as soon as possible.
Soooo yeah. Long response but I hope some of it was useful. Your wife is really lucky to have a partner who is making an effort to help and understand. Having support is so important. I wish you both luck! ADHD is not fun but there are ways to make it much easier. Feel free to AMA if I can help you in any way!