I genuinely do not know if AIBU. I accept that I am being ridiculous. I also understand that my attitude towards food is probably not healthy.
My mother has taken it upon herself to start buying me groceries. I don't ask for it and I don't know why she is doing it. She says it is to help me because I am busy and stressed with my new (I am busy I am not stressed, I am enjoying my new role)
The problem is she is buying food I don't especially like or enjoy, and then she gets upset when I don't eat it.
I have tried telling her I don't like the food she is buying. She got annoyed that she was wasting money. I have tried thanking her and pretending I like the food she buys, but then she will root through the freezer and find it uneaten, or she will see the kids eating it and get upset.
I have tried saying yes when she asks me what I want and being very specific and explaining that whilst other things are very similar I do not like the similar things I only like the ones I ask for (think frozen ready meals vs fresh ready meals or porridge you cook in a pan vs those instant pots) She will find something else on offer and get that instead. I have tried offering her money for the food so she can buy what I actually like without feeling like she has to find things on offers, but she refuses to accept it.
She is now not speaking to me after offering to call into a shop she was passing that she knows sells protein bars I like. I insisted on giving her the money for them because, as far as chocolate goes, these are expensive.
When she dropped them off, I thanked her and said I didn't have any left because DD had melted my last one by accident after putting a hot kettle right next to the box I usually keep them in, and I don't like them after they have melted and reset because the texture changes. She then told me she had carried them on top of hot pizza 
I didn't get annoyed (or I didn't show I was annoyed), I laughed and told her it was fine. DD likes them when they are melted; she will eat them. She left without speaking to me, and then I was inundated with text messages about how I don't appreciate her and she is only trying to help, and why am I making it so difficult for her?
Bear in mind, I am not asking for any of this food. I keep telling her to stop buying me food because of how fussy I am. I honestly don't know what I am supposed to do. How do I get her to stop?