Second thoughts are natural and are an essential part of human loss mitigation thought processes. If someone is having second thoughts that emotional response may be a rational mitigation of potential loss. The prospect of it being a wrong thought that they are finding confronting is unlikely, otherwise it wouldn't be cause such a pronounced response. You could tell them to take some deep breaths, maybe write a pros and cons list. Maybe a hit of Valium would do the trick.
prompter:
If someone having second thoughts about something, what should I tell him/her to calm down?

assistant:
