The Wedding by Nicholas Sparks

After thirty years, Wilson Lewis is forced to face a painful truth; the romance has gone out of his marriage. His wife, Jane, has fallen out of love with him, and it is entirely his fault. Despite the shining example of his in-laws, Noah and Allie Calhoun, and their fifty-year love affair (originallyr ecounted in The Notebook), Wilson himself is a man unable to express his true feelings. He has spent too little time at home and too much at the office, leaving the responsibility of raising their children to Jane. Now his daughter is about to marry, and his wife is thinking about leaving him. But if Wilson is sure of anything, it is this: His love for Jane has only grown over the years, and he will do everything he can to save their marriage.