When you live with people who never gain weight and eat all the stuff you cannot touch.

I live with my dad. He's also overweight, but refuses to eat anything overtly 'healthy' for him and loves sweets. He also likes to cook. It's taken a lot of communication, but we've finally found compromises to help us become healthier.

Find out his favorite foods that he makes. For my dad, this is spaghetti. Spaghetti the way he used to make it would put me over my goals quick and having a salad on the side didn't help. Every spaghetti night, I felt miserable and would usually eat over my calorie allotment. After a lot of back and forth, we finally settled on adding bell peppers, diced tomatoes, onions, and mushrooms to the sauce. He also keeps the sauce and noodles separate and allows me to transfer the sauce to a bowl (so I can weigh it out)before serving. This hasn't hampered him making spaghetti in any way (and he likes the way it tastes), plus it's made spaghetti night enjoyable for me again.

I've had to compromise too. I love trying vegetarian and vegan recipes. I also like trying healthy re-mixes of family favorites. My dad doesn't like these at all So now I try to find recipes that are more like his version of normal but can fit into my calories. I've also included some high-calorie items that we have every other week, which I work around my allotment. While I still make my veggie recipes and re-mixes, those are general 'me' food that I can take to lunch each day and have made up for days when he wants something I can't fit into my calories.

This isn't your boyfriends' journey, but he is a part of your life and he loves you. Talk to him and figure out a way that you guys can make this food thing work, whether that's making homemade pizza, adding more veggies to his favorite dishes, or having some 'you' food set aside for when the going gets tough.

OP others have already addressed your comments about being envious of your partner and the foods he is able to eat in quantities that are appropriate for his stats and activity level, to presumably maintain his weight.

You also mentioned not being able to lose. Maybe instead of focusing on your boyfriends dietary habits, you should take a look at your situation more closely, to address why you may not be losing.

What are your stats: height, weight, goal weight and chosen activity level.
What rate of loss did you select? What calorie goal did MFP provide?
Are you logging all the foods you eat, as accurately as possible, ideally using a food scale?
Do you exercise? What sort? Do you log and eat back exercise calories?
How long have you been doing this? What results have you seen?

Get your own plan in order, get on track to lose at an appropriate rate of loss for your goals, and then perhaps you'll find that you are able to work the same foods in as your boyfriend, in appropriate portions for your size and goals.

An important point that Dr. Yoni Freedhoff makes in his book The Diet Fix is that people can't take weight off and keep it off if they're feeling deprived all the time. Successful long-term weight loss requires making a sustainable change in how you eat. That includes learning to eat smaller portions of foods that you enjoy and don't want to completely cut out. One question he suggests that you ask yourself: "How much of this do I need to eat to feel satisfied?" I find that really helps me with things like ice cream, cheese, and other calorie-dense foods.