The man talked of making some cursed and marmalade-style fillings at home to take to his sister’s bakery to reduce her workload while she finds an assistant.
This was opposed to him being bothered about her actually eating. The issue escalated in him shouting at her to stop eating because she continued to use her fingers on four occasions.
His girlfriend responded that she felt she was being fat-shamed, but the OP insists it had nothing to do with her weight but was contaminating his food.