We might refer to the Willowherb flower essence as the "I accept essence". It is to help us appreciate that "our way" is exactly that and others need to find "their own way" after all - many roads lead to the same destination. It prevents us from wasting our energy on trying to "convert" people to our way of thinking for they are simply on a different vibrational frequency than our own.
A feeling of letting go and peace. Physically for areas of our body experiencing congestion.