How to set boundaries with bf and myself around food…

Sorry in advance for the essay… In January 2021 I was in the best shape I’d been for ages, was working out and eating healthy. Then I got into a relationship… I have gained back all the weight I lost plus a lot and am now at my heaviest. It’s really getting me down and I can feel myself spiralling back into disordered eating habits. It’s starting to affect my relationship too as I wonder if he’s still attracted to me all the time.

I know it’s not all down to him and I don’t resent him at all but I know that part of it is that he’s able to eat whatever he wants and not gain weight. I struggle with anxiety and binge eating disorder and find it really hard to say no when he’s getting takeout multiple times a week.

I feel like I need to set some boundaries and talk to him about it but don’t even know where to start. But I also feel like I need boundaries myself. Has anyone experienced something similar and has any tips?