Well... I don't know anything about diabetes. But I do know how difficult it can be to change one's eating habits when one is alone. And I recall your niece is a very important person in your life; & she's leaving for Los Angeles soon for 6 months.

I know you're in the U.K. And I don't know what may or may not be available to you there. But I wonder if there would be any possibility of you finding some sort of diet or diabetes support group you could join. Having other people around you who are experiencing the same struggles can be a blessing. I wish you well...