Sure! Here's the requested content in spun format with synonyms:
Candy is crazy about Finn and Ferb.
Cara has strong feelings for Finn, and also Frank.
Finn captures the love of Cassandra, and also Felix.
Candace being with Phineas and Felix.
Finn means the world to Candy,
and Frank.
Cassandra is emotionally attached to both Fred and Foster.
I hope you find these variations helpful!