I'm guessing he's eating comfort food following his health crisis. It doesn't make sense, I know. My DS, after having serious heart problems then the install of a heart monitor, is doing the same thing.  He knows it's wrong but can't stop.

I also have a DH who wants an eating buddy.  Like you, I'm careful to eat healthily due to health and weight issues.  He's constantly bringing me food and wanting me to eat more with him.  It's not junk cuz I don't buy it but it's excessive food. I realize he's bored and a little lonely tho he doesn't want to go see others.  The only place he wants to go is fast food or the casino, ie, excessive food or money

 Sigh...

You describe my DH too. I make a salad, he makes grilled cheese.  Baked chicken for me, pasta with jar Alfredo for him. He might have a protein smoothie if I'm having one. You get it. 

Typically we'll eat dinner together, and I usually cook, so I can control that and sneak veggies into the meal. It's like cooking for a toddler, and I'm a bit of a foodie trying new recipes. If he doesn't like a meal, he makes a pbj--it doesn't hurt my feelings--it's a HIM issue.

But most days, he gets fast food, donuts, ice cream if he goes out for any reason. At least he's stopped bringing "surprises" home for me.

And he has serious health issues including diabetes. But bad food habits are deep seated, with a mental health component, I am convinced of that.

I can't control what another adult does. But I do control most of the groceries and at least one meal a day. He doesn't complain, fortunately. It does make my commitment to my own health difficult some days.

And it's frustrating. 

I'm the "worse" eater in my relationship, but only by a little. My SO can't have any extra weight or he becomes diabetic so he actually eats only meat and vegetables and a little fruit. It drives me crazy when he fusses at me for eating carbs but it would really drive me crazy to live with someone who only ate fried foods. Maybe try making your good food with a nice presentation and go on about how good it is while he eats his brown greasy stuff? 

Cuts down on the unhealthy junk food latter in the night.  If he didn't eat healthy he would be eating more unhealthy food so you are helping him.  If he's on a suicidal by food mission. Only he knows 

I think you need to gently tell him that although you respect that he takes comfort from food, his food choices aren't yours, so don't bring any home because you won't be eating it.   He may want a partner in crime but the sooner he stops doing this, the better for his health, and yours! 

If he knows you won't eat the "extra" he brings "for you," guess who gets even more goodies?

I think it's strategic, in addition to wanting a junk Food Buddy. A lot of people are actually alcoholics but with food, not alcohol. It's more socially acceptable to be heavy/obese than to reek like booze & slur your words, drive drunk, etc. Both are killers, but one is legal to all ages. 

While you can 100% quit alcohol and abstain, food is a tiger you have to let out of the cage three times a day. So in that regard, people who are using food in an unhealthy way have a super-difficult path to positive change because they continuously have to make food & quantity decisions, every day. 

I get this because my husband is not the healthiest eater either. He is a great cook and does most of the cooking, so I eat small portions. He is a little 'fluffy' and I am very small...he has not made the correlation between our eating habits and our sizes. I take lunch to work and make very healthy choices when not in his presence. He has treats at work and when not in my presence. I wish he would do better, just because I love him and I want him alive and healthy, but I know that it is not up to my wishes. I do try to cook healthy choices and make healthy side dishes to go with our meals. That is about all I can do.

Chef brings home lots of booze, desserts and steak, oil and garlic pasta and cooks for a friggin ARMY  even though there are just the two of us.   I did take over the kitchen between rental rehabs, which was great but he's back in the kitchen again with the boatloads of food and horrendous kitchen messes!

I think they also have toddler mindset.   In addition the hurt from PASed out skids causes them to self soothe AND they want you to be out of shape so you "won't go anywhere."   Chef was resentful a few years back when I lost 35 lbs which was an absolute climb up the Matterhorn for me.  He said absolutely nothing and tried to sabotage me at every turn.

Sometimes, our partners sabotage us.. maybe because they want to excuse their own poor habits.. so he brings things you find hard to resist.

So.. in your case.. it's not just his poor eating but he does things that cause you to deviate from your diet.  I might have a direct conversation.. asking that he specifically NOT bring home things for you.. and when he does.. I would bin it immediately.

My DH eats like a 12-year-old boy and doesn’t do any type of physical activity other than move from the couch to the chair and back.  He’s on several medications for high BP, pre-diabetes, asthma and allergies.  I don’t really cook anymore since we are all on different schedules, but when I do I make food it's what I enjoy eating and figure he can either eat some, starve or go make one of his high sodium microwave meals.  I learned a while ago it’s not my job to manage my DH’s health, he is a grown man, and his learned helplessness routine is tired and worn out.

Oh yes! I posted a lengthy vent about it not that long ago. In May, DH was diagnosed as type 2 diabetic. He has cholesterol on the high end and had to have two colonoscopys. One was the take out a massive polyp. DH was scheduled to go for blood tests after four months to get checked on his progress, but he canceled his appointment to give him more time. I tried to help him but he eats like an asshole. We're talking about a man who won't eat brown eggs. I'm not kidding. He won't eat the same meal two days in a row, so forget leftovers even if he really likes something. He has this thing about food prep so forget that. He eats out everyday. He brought home instant rice cups that take one minute in the microwave and he found that too much food prep. He's back to hot dogs every day, processed food, instant meals in a cup and thinks that t throwing some processed chicken strips on top is helping him get his protein. It's so frustrating. I've been preparing for a long time of being a young widow. Even the kids make comments. DH works out constantly, so he thinks it undoes everything. It's hell when a family event is planned and it's at a restaurant because DH has to examine the menu days in advance so as not to be faced with "anything weird." If there isn't basic crap that a picky brat won't eat, DH makes an excuse to not attend. 

It's funny because for years I thought that DH was feeding the SKs the Disneyland Dad Hedonistic Don't Leave Me Diet to my SKs. When DD24 was growing up, DH and I did not agree at all on feeding her. I ultimately told him to not ever feed her. He'd have crap waiting for her every single day after school. It drove me nuts. Now that all of the kids are grown, I realized that for DH it's not a Disneyland Dad issue at all. It's a him issue. I've tried to help him but I gave up. If he wants to be a 67 year old walking around with unmanged type 2 diabetes and high cholesterol, there's nothing I can do. 

DH and I eat pretty darn healthy overall and always have. However, DH used to have a really bad habit of snacking and especially late night snacking: chocolate, ice cream, chips were standard. He drank a lot of beer too, not every day but enough. He was boarderline diabetic, but knew how to keep just under that line; he also always exercised a lot. Then he had his crisis this summer. Has been seeing a therapist regularly since. His eating habits have improved greatly. We no longer have chocolate in large quantities in the cupboard, or half-gallons of ice cream, bags and bags of chips. Luckily I am not a snacker and these things don't tempt me (I used to have to hide chocolate from him on the odd times I would get some for myself, or he would 100% eat it). He'd get up in the middle of the night and eat too.

I couldn't really talk with him about it b/c he'd get defensive. All part of his issues that he wasn't dealing with, absolutely. I have had a chocolate bar in the cupboard for over a month now (I've not wanted to eat it yet) and he's not touched it. It's all about if he wants to improve. You can talk with him, but just be sure not to judge. If he gets you the "treats" then just don't eat or drink them. Repeat firmly that you do not want them. Hopefully he sees a doctor every year?  This might help, but no guarantee...