Hi there -
If you haven't already done so, I would seek a consult with an endocrinologist, since there has to be a metabolic/glandular component to this. You're doing everything right but your body isn't responding the right way. There are a number of endo-related issues that can cause this sort of problem. You've done well with the triglycerides with medication, but if you could start to lose instead of gain weight those numbers would likely go down a lot more. As it stands you're at risk of developing
diabetes, among other things, so if you can find an endocrinologist to take an interest in solving this it would be a huge advantage to you. Meanwhile, keep up the great work.
Hope this is helpful. Good luck to you and please follow up with us as needed.