What's the Name of That Book??? discussion

This is a real life story (possibly in UK) where the woman used to meet the man everyday on the train (travelling in the same compartment), she first wrote a letter to ask him out but he was committed at that time. After a year or more, he wrote to her asked her out for a coffee.
They both got engaged and the woman wrote a book inspired on their story.
I absolutely do not know the title, just the premise of the book.

Here's a link to Laura's suggestion:
The Note by Zoë Folbigg

Emily wrote: "Here's a link to Laura's suggestion:
The Note by Zoë Folbigg"

Thanks a ton! This is the book I was looking for :D