How do I handle people trusting my models too much?

You have reached a level where what you build actually moves decisions, and you have noticed something many never do: people trust your work more than the work may deserve. A model is a confident-sounding thing, and confidence invites belief. That you feel the weight of that belief is not anxiety; it is conscience, and it is exactly what should sit in your seat. The danger is not your models being wrong sometimes. Everything human is wrong sometimes. The danger is your models being wrong quietly, wrapped in a certainty that stops people from asking questions. Your job is not to be flawless. It is to keep the humans around you awake, aware of what the model does not know. So make honesty about limits part of what you deliver. Alongside every result, say plainly where it is shaky and what it should not be used for. Teaching people to doubt your work in the right places is the most responsible thing a person in your seat can do. That care is why the trust is warranted at all.