Human Lass has to mentally contend with the fact she's been eating the body parts of COGNISCENT beings and their pets, since she's been refusing all other foods, and the plants on this planet are almost all cogniscent. One has to imagine the mental collapse as she recognizes the pieces she had on her plate not long before, with the surgical procedures she just witnessed on the plant-beings.
Here's hoping therapists can heal a full mental collapse.
For two days, the dangerous, baby-eating mammal refused any and all food. Only when they patiently explained the harm Lass was doing by forcing them to interact with other baby-eaters, did she relent and force herself to ingest soups. Disgusting soups to the both of them, now, but as long as it didn't contain anything she could recognise, all was nominally well.
It was clear that something had finally sunk in. It was also clear that that nugget of new information was devastating.
The compromise, for Lass, was fungus. Fungus had yet to show any kind of evolution towards cogniscence, sentience, or any imitation thereof. It was all natural and did not contain anything like nerve endings. Therefore, nothing got hurt.