What's wrong with The Idea of You? A Commentary 

I think the end works. Because the book is a book and the movie is a movie. Also Hayse did tell Solene that after 5 years to give Izzy the chance to finish high school, to meet again. And even though Solene told him to accept happiness if he finds it Hayse went back to Solene because true love finds it’s way no matter what. So for me The idea of you movie is perfect.