Rosie Dunne by Cecelia Ahern (2005)
Rosie and Alex are meant for each other. And yet life keeps getting in the way. Follow the pair through letters, notes, instant messages, and emails. Laugh at their correspondence with each other and with their friends and family.
These childhood friends become long distance pen pals when Alex moves from Dublin to Boston. Plans to reunite are constantly thwarted. College happens, then marriage, births, and deaths. And yet they keep in touch. Watch Alex and Rosie grow from childhood to middle age and find out if fate helps them finally get together.