Status Updates From The Blue Sapphire

Reading for my Retro Reads author challenge. I was a teen when this first came out. i must have loved it, judging by how many times I reread it.
I'm interested to see if I can figure out why I liked it so much. I remember nothing from 60 years ago, so this will be new to me.
I can already tell that Julia's fiance is a drip and that he will not be the guy she ends up with. I'm betting on the guy she just met.