BDD probably isn't the best forum for this type of discussion. You might have better luck if a Mod moves this to The Dark Side.
As for W/D tips...lots of advil, try to keep entertained with light-hearted bullshit movies etc. Depression during W/D can be a bitch, especially after the acute phase, but the fact that he has a supporting partner to help him through the bad times is definitely an advantage. Good luck.
If any of this is considered triggering material, please kindly delete it, as apart from some edits I replied in BDD, and I'm not fully familiar what is considered a trigger on TDS.
On topic, loads of hot showers/baths and valerian root tea (buy the shredded stuff for making tea, way more effective than the. "extracts" you can buy in health stores). Imho the latter is preferable to real benzos in this case, as suboxone WDs can last quite a while if you've been on it for longer time spans, and you REALLY don't want a benzo habit. Those sneaky things help great at first, but tolerance sets in very quickly when using daily, and benzo withdrawal is objectively worse than opiate withdrawal. Seizures aren't fun, and there's nothing that really helps except more benzos.
So I disagree with the advil, valerian root and chamomile tea may be weaker, but you don't run the risk of swapping one addiction for another. This tea combo is also great for combatting troubles getting to sleep. I like to complement it with low dose DXM (120-150mg/55kg, yes, I'm skinny as fuck) once a week to take my mind off the symptoms, and 50mg benadryl every night to help me sleep (25mg will suffice at first, tolerance builds after a while, but not too quickly). Read up on these substances first, if you decide they might help: both are very powerful drugs in higher doses.
DXM (Dextromethorphan) is a dissociative and can be fun tripping on (if you don't mind the somewhat heavy bodyload and next day afterglow a.k.a. contented laziness and somewhat slowed down thoughts, but in a comfy way). WARNING: for these purposes, only buy products that contain only DXM as the active ingredient. Mixed products will often lead to complications ranging from nausea to brain cell death up to terminal liver damage.
Even when withdrawing from opiates, a high 2nd / nearly 3rd plateau can be enjoyable, simply because you're somewhat dissociated from your bodily aches. Combined with MJ, it feels like a completely new drug, extremely interesting synergy.
Simply google for "DXM plateau weight dose" and use BL's search engine for more infos, trip reports etc. Don't overdo it please, the rule is to wait one week per plateau of the last trip. Of course, I didn't heed this during my first real heroin WDs and spent 4 days literally dissociated from my body and the rest of the world. My brain took a good month to function properly again, at least I think that now...
Benadryl on the other hand, or rather its active ingredient DPH (Diphenhydramine) is a deleriant. I'd only take a high dose of that if it was forced down my throat, no way would I actually want a trip like that. 150mg will get you a nice body buzz, higher doses tend to lead to hospital stays or jail, and you don't even remember wtf happened, because you were delirious the whole time (you can check trip reports on Erowid (just google). Examples for other deleriants are datura and other anti-cholergenics. Interesting reading, but way more horror stories than good things. Still, great for sleep and opiate potentiation at low doses (DPH, I mean).
You already mentioned exercise; that's perhaps THE BEST WD REMEDY there is, release of endorphines ftw.
A healthy diet will also help big time, provided his appetite plays along. Personally, I've always used marijuana for the munchies effect, but that isn't for everyone, so protein shakes and loads of veggie soup are an alternative, easy to keep down and nourishing. Some vitamin supplements can also help, although fresh veggies and fruits would be preferable, as the vitamins in these are( absorbed more efficiently. Try to keep as close to his "healthy" weight as possible, this is really important. I lost about 5kg the last time I withdrew, I looked like a skeleton until I had regained my usual skinny frame (took half a year, I don't always eat healthy).
Oh, and get some cheap loperamide (generic immodium) against the shits. Also, high doses will nearly eliminate all WD symptoms if he feels he needs a days break from everything. Takes about 2 to 3 hours to fully kick in, as a starting dose for overall relief I'd suggest 40mg, that's the lower end of doses I can recommend for complete relief, it really depends on the persons tolerance, but I've taken up to 100mg in the past, all WD symptoms were gone for a day, and the constipation isn't worse than that from other opiates. In fact, 4mg of subutex blocks me up far worse than 60mg loperamide, but afaik there aren't any official test results and I don't know your spouses tolerance, so better start low (30-40mg are perfectly safe, even for opiate naive folks). Lope lasts a full day, so redosing is easy, just keep the long comeup in mind and redose after 3 hours, if necessary.
That's about all I can think of right now, apart from one last thing.
Take good care of yourself too. You may not have a habit, but you're still deeply involved. This may be called co-dependency, I'm not quite sure right now, but I suggest looking into the concept.
Please make sure that YOU have someone to support you during this hard time, be it a good friend, an understanding relative or a professional. Your wellbeing is just as important as your spouses.
All the best & lots of strength, to both of you.