Sangfroid is professional conscious emotional detachment; approaching a problem or trying situation with calmness and dis-passion; or maintaining composure in difficult times.
A healthy level of conscious, professional detachment is important to maintain concentration and enable rational thinking/problem solving especially in emotionally charged and stressful situations.
Detachment explains why it is often easier to solve someone else’s problems. Because we are not enmeshed in the problem or caught up with the outcome, we can devote our attention solely to the problem.
Conscious detachment means being mindful of our emotional responses in a given situation, so we can consciously manage them or take steps to de-fuse them.
Management techniques could be: to remind ourselves that the problem is not the person; to re-focus on the greater goal; and to reframe personal attacks as their response to fear such that it is about them and not us.
De-fuse techniques could be: to politely take a break from the situation when we recognise that we are becoming overwhelmed. Or use humour if appropriate.
This is not an outright denial or suppression of our emotions. That would be unhealthy.