How to take responsibility for myself as a cancer patient?

I am a cancer survivor that has been in remission for the past few months. I have been advised to follow a strict organic, all-natural vegan diet with lots of juicing. My aunt has been nice enough to take care of me and make my meals (I don’t care for cooking), but for awhile now she stopped cooking for my diet and started cooking unhealthy meat based meals because that’s what the rest of our family eats. Our family visits a few times a month, but it’s not too often.

A conversation often goes like this:
She asked, “Do you think it’s fair they have to eat vegetables just because of you?”
And I’d yell, “Well, I’m the one with cancer! Why not?!”

It’s really awful.

I know I am an adult and should be able to make my own healthy meals without depending on her, but for some reason I don’t have that motivation in me to learn how to cook. I’m too tempted to eat when’s left in the fridge and I hate cooking. Often I blame her for prioritizing our family instead of my vegan diet and it creates tension in the home.

Please let me know what I can do to stand up and take responsibility for myself. Thank you so much.