As a former ED sufferer (although not T1), I empathise with your frustration.
Bearing in mind you say you sensibly always take your insulin, is your T1 a fundamental part of your problems with eating, or is it just*** an bit additional part of your life that you have to take into account in all you do, and how you generally live your life?
The word "just" above isn't to trivialise your T1 or ED, but trying to work out how fundamental it is to your ED, as opposed to another complicating factor.
Have you had general help for your eating disorders over the years, or are you recognising various stages and coming to a point where you feel it's your time to take a different path?