Re: A better movie would be:

If there are honest, healthy novels about inter-generational relationships with girls, I have not yet found them. Any suggestions....anyone?

There is, oddly enough, several sci-fi and fantasy works that depict adult-child relationships in a neutral to positive light, but unfortunately this is never really focused and more mentioned in passing. The closest to a literary novel that portrays a positive man-girl relationship is probably Dream Children by A. N. Wilson, although it is often marketed as being a satirical work. I wonder . . . There are novels that portray adults who fall in love with a child, though for one reason or another their love is unrequited. The most prominent example would be Gabriel Garcia Marquez's Of Love and Other Demons.