My new boss said, it is one thing to record positive feedback in the notes of a telephone conversation and another to receive an email. When one of my clients takes the time to mail a thank you card that is something else.
I feel humbled by the recognition and thankful for being able to make a positive difference in someone’s life.
theINFP 
In this day and age that is a genuine treasure, that someone would take the time, meaning your effort was highly valued, how wonderful to receive.
Thank you, I agree.
Good for you – and good for her!
It is amazing what a thank you does to another.