It just occurred to me that Horo might be really afraid and is doing this because she doesn't know what else to do. She saw that dream of choosing Lawrence but the man turning into nothing but bones. And now it's also more and more evident they might be nearing her village and thus the moment she would actually need to make that choice in practice. Maybe she's now pushing Lawrence away exactly because she loves him and doesn't want to go through the suffering of losing him inevitably later when she would love him even more.

Amarty might be nothing but a tool that suddenly presented itself to Horo for her illadviced, painful, and far too hastily constructed plan.