Why?
The tone of the letter was studiedly cold.

Why?
There were a few more lines to say that Jack was coming in to eat Christmas dinner with her and that she would sing If I Were a Voice.

He was not super-subtle and yet something in this letter made his throat fill and his head a little _dizzy_.

If it did not mean that she had broken with King, then truth could not be conveyed in lines of black ink.
He tore open Jack's letter.

It was short and to the point.
"DEAR HARRY: If you can get away come back to Marmion and see Mary again.