I eat OMAD (one meal a day) and have no hunger between meals.
You fix 3 out of 4 of his meals so it is doable to make it where at least 3 of his meals are keto and will keep him satiated 
may be he would rather have a keto friendly snack if you pack it for him
My husband still thinks this is a stupid idea for ME, let alone him. Even if he’s theoretically satiated and not actually hungry, he’ll still stop at that drive-thru out of habit. I know him well enough to know this. Unless he gets on board mentally first, he won’t bother to even try to change his habits. He’s never listened to me about his water intake versus his diet soda intake, no matter how many links to studies I show him about either one.
Same thing with his sleep habits (he has sleep apnea but won’t admit it) and a few other health-related things he won’t acknowledge. I try to urge him without being naggy about it, but as has been said many times in this thread… he’s a big boy and has to make his own decisions ultimately.
And, UNTIL he’s on board with this, I just don’t want to make things worse. That’s pretty much all I’ve been asking: Should I continue to avoid adding fat to HIS food if I can (without jeopardizing my own)?
I think that, because his keeping the carbs is going to interfere, I should continue as I’ve been doing and keep his own food less fatty than mine. And I continue to hope he’ll see my continued success and want to share in it with me! 
He may just have to hit rock bottom for himself before he can make a decision to do anything proactive. His blood sugar might not be in the pre-diabetic or diabetic range, but I bet his doctor would agree he is Insulin Resistant. It’s just a matter of time.
My hubby knows he can control his diabetes with diet and exercise because he’s done it before, yet he is on three blood sugar meds (one is VERY expensive and our insurance won’t pay for it). He’ll eat low-carb if I’m doing the food prep, but the trouble is he is currently on the road (we are both truck drivers), and I’m not at present because I have a bad knee (although my weight-loss has caused a huge improvement there). Once I’m back out there with him, we will both be keto, and once he realizes how much better he feels, I don’t foresee a problem with him staying that way.
Have you ever seen the presentation Fat Chance: Fructose 2.0 ? Dr. Robert Lustig lays out a convincing argument for sugar being addictive in the same way as cocaine with regard to brain chemistry. My own sugar addiction is not “cocaine level,” but it’s pretty bad. I have decided I have to stay away from the stuff for my own good. Luckily, with keto, it’s not hard at all.
Would he do it for just a week or two? Just to see if he can pass up that drive thru? As a challenge or a bet maybe?
Probably not. It’s hard to change the habits of someone who truly doesn’t see a problem in the first place.
I suspect it will take more weight loss on my part before he’ll acknowledge that there is something to this thing after all. (I’m only 3.5 weeks in.)
My problem is my kids. They both have constipation issues and after reading some of the side effects are constipation I decided not to have them join my journey. My husband does not eat keto either but he has always been in good shape. So I give them their regular meals for lunch and breakfast while I eat keto. Then we share a dinner we can all eat together. So I try and just do meat and veggies. Getting more fat in earlier in the day. Although still very new so don’t now if this will work long term.