HI! I am 47 and have had hashimotos hypothyroidism since I was 14. I completely understand where she is at! I didn't really start feeling better until I was in my 20s and finally took it upon myself to get better and figure it out as it was killing me, my Dr was brutal!
First thing is you need a DR that will test all thyroid levels including antibodies. FULL THYROID PANEL! TSH free t3, free t4, reverse t3 and both sets of antibodies. She needs to know all of those numbers because unfortunately different levels and combos of levels mean a million different scenarios and how to treat.
10 years later these things were the key to my recovery ( still have it of course but I feel good) minus the perimenopausal BS right now which also is a lot worse when you have hashimotos! I am on t3 and dessicated thyroid hormone NOT Synthroid because I cannot convert t4 into t3. This right there helped so much!
Next one is NO GLUTEN!!! My inflammation dropped ten fold when I gave up gluten, I actually for the last 10 years now do not eat any grains at all which has helped even more.
Third move your body even when you do not want to!! I get up at 4am ( and yes had 2 kids at the time, full time job on my own all of it ,I get mom life and busy)and I walked every morning. I have not missed a day because when I do oh I feel it!!!
But I then took it too far and worked out like a maniac, pushing weights 6 days a week, HIIT, Jogs, you name it and I crash and burned and gained weight fast. With hashimotos our body stresses easily! Less is more. So nice easy walks morning and night, with weights 3-4 days a week MAX, that seems to be a sweet spot for many of us Hashi warriors.
Caffeine Is a personal thing, I have coffee in the morning and maybe another by noon and that is it, I do not live off it because once again we will stress our adrenals and then we go into flare ups.
I also have PCOS, insulin resistance and allergies and the only thing that made that better was what I put in my mouth! More like what I didnt! If I even take a bite of a piece of bread, or have processed garbage I pay so bad that I cannot even move my fingers in the morning. It is not worth it to me. Do not go low low carb as we need the carbs for our thyroid, but we do not need excessive. Keto worked against me, it was too much saturated fat and I inflamed. So I eat tonnes of veggies, fruit, lean proteins, and Greek yogurt ( Dairy bother some autoimmune people so take it out and see if it makes a difference, it does not affect me).
The best investment I made was an infrared sauna! If you do some research you will see how wonderful it is for detox and we need to detox our inflamed bodies!! I am in mine 2-3 times a week without fail.
BEDTIME ROUTINE!! Stick to it! Sleep is key - mine sucks right now with the hormone BS but I have turned down so many things because I value my sleep like GOLD! lol!! You start to go down fast if sleep gets put to the side!
AS far as supplements go, honestly you really need to get a full blood panel done before you start adding things. But VitD/K, B complex, magnesium and milk thistle I do take every day. I also use DIM. I use some other things to but it is for my personal situation and could be horrible for someone else.....
I have been at this for so long and have tried so many things and in the end everyone of us with an autoimmune condition has to find what works for them....I am part of many groups to always learn and listen to podcasts, it is a constant battle, and unfortunately with an autoimmune condition you usually get a second and sometimes a third.
I have 3 now, and also horrible genetics but I refuse to roll over and give up, but I know that if I had not stayed on top of my health I would be a wreck.
It sucks but I have total faith that your wife will feel better with the above things, full blood work panel - from there correct meds and supplements, no gluten, detox with sweating, move the body.
As far as peptides go, I have "researched many" MOTS-C cycle it and love it, BPC for the inflammation including the gut ( key for hashi)AOD, FRAG, Ipamorelin, Thymulin, TB500, SS31. BUT adding these to not having your ducks in a row as far as already doing everything possible first, these will not make things "better".
You need the groundwork first then you get to sprinkle the "research". I also have a leptin deficiency, to put it in lame terms as it is complicated to explain what happens in my body.
So I just started Jul6 " researching" Tirz and WOW, So many benefits past the scale. Inflammation of brain ( mood) body ( aches and pains), food noise is GONE, which I have battled all my life which turned into a horrible eating disorder.
I have lost 15 pounds in 5 weeks, and I only had the vanity 10 to lose BUT I was starting to gain as perimenopause is really affecting me so I think I would have kept gaining ( plus lots of inflammation weight aka water) if I didn't take the leap of faith to try these.
But I am a happy person again, I laugh, I enjoy little moments, ( Mood is a biggie with thyroid imbalances I was on the antidepressants and the Adderall but it was too many swings up and down for and I had to stop) I do not ache and I will die if these peptides vanish ( hence my stockpiles).
I am so sorry this is so long, but just know this isn't a death sentence, I played Ringette and hockey at college level for years, coached my kids in their sports, and kept up to them and still can beat them

. lol!! We can get you better!!!
I could share a million more tid bits as there are so many things...... but if you need any help or questions, please ask me. I would love to see her blood work numbers when she gets results ...I have helped so many women with it, as Drs do not know enough and use " normal ranges" instead of optimal, and only try one thing or just " deal with it"......also my millions of hours of research over 30 some years I need to share it!! There is no better feeling than helping someone feel better!! I wish you all the best!!
*** Remember this is what worked for me but there are many others out there that some things above won't make a difference, or they manage it completely different and feel super! We are not cookie cutters!