This story sure didn't age well. The story itself could work in any time setting, but the characters and their actions and reactions don't fare well in this day and age.
First of all, the story is written in third person, but from the heroine's perspective. Since said heroine, despite being twenty-two (or so we're told) comes across as childish, immature and rather self-absorbed, so we don't glean much about the hero or his possible inner workings from the narrator.
Because we're not privy to the hero's inner voice, his character and his intentions remain (mostly) a mystery, and the final revelation about his true feelings doesn't really work and seems rather unbelievable or implausible.