I think it's called "She Loves Me" and is from a Broadway musical (of the same name?) that ran in the 60s. The original was not in the "he" gender, though that doesn't really matter. Your version might have come from a female vocalist who changed the pronoun.

If anyone knows of good websites for Broadway show lyrics, it's worth trying there. As I say, it was a hit about 40 years ago (can't believe I can remember back that far!!) in the middle-of-the-road-ballad arena, not as a pop song.