I am a diabetic, and it took me forever to find a doctor who actuall BELIEVED me when I said I gain weight at 1500 cal/day. Until this doc, who specializes in diabetes and PCOS, listened to me and ran the proper tests, I was "alone" in everything I ever did, and once put myself on a very strict 800 cal/day diet that was NOT an IP type diet and literally starved 85 lbs off of me out of desperation.
So I feel ya!
The first weight loss that really worked for me that wasn't starvation, was Atkins. But like a lot of Atkins diet followers, I just quit losing after a while.
I have seen 3 different dietitian/nutritionists in my lifetime, plus one horrible diabetic clinic day after I was diagnosed. They DON'T GET IT! They want us to eat a "balanced" diet, but to eat balanced, lose weight, and deal with diabetes (I'm not on insulin) it's back to a starvation diet, basically. And I wound up maintaining for a lot of years on a 1200 cal diabetic diet, rather than ever losing any weight. Dietitians are not for everyone, because every one I've seen wants me to eat the calories that the chart says I should eat for my weight, which starts out at about 1800 cal/day. I have NEVER in 10 years eaten that much on a daily basis, and if I did I'd be gaining a pound a week, not losing it. They don't get it. They use the food pyramid, and want me to eat a ton of grains. I'm super super insulin resistant and I can't eat more than 1 piece a bread a day. Ever. They think I'm lying.
As for too much protein. I talked to my Dr about this, because I was doing Atkins. A "healthy" person should have about 1/2 gram of protein per pound they weight, per day. I'm 250 lbs now, so I should have around 125 g protein/day. I actually make sure I try to hit that target using IP. You can eat a WHOLE lot more protein that than per day without adverse side effects if you have healthy kidney and liver. On Atkins, I was doing about double that.
I hope you get everything straightened out and that you are able to maintain properly. It's not easy, but it's doable, once you get in the right mindset. I know it's possible to maintain without exercise because I tore some ligaments in my shoulder and couldn't do anything but walk for exercise for 2 years, and I didn't gain weight. I averaged the 1200 cal/day, and very few carbs (under 75 g/day). It's a matter of rethinking food. It cannot be used as a crutch. I had a long road to deal with that!
to you!