Boy Trouble by Rosamond du Jardin (1953)

An Embarrassment of Riches ...

All the fun of high school graduation and that special summer before college are heightened for Tobey Heydon when dashing Dick Allen adds his attentions to those she is receiving from her favorite young man, Brose Gilman.

And the plot really curdles (along with Brose's feelings), when Tobey meets a handsome artist who seems to be the object behind her non-objective paintings. 

But Brose gets his revenge, and it's not only sweet, it's hilarious.  (from the back cover)