Coendara and the princess didn't get married. An earlier chapter said that the marriage was delayed again and again then she returned to her family. In this chapter, he even calls her his "fiancee" not his wife.
You know, Aidra doesn't really look happy to me in the flashback scenes this chapter. She smiles, but her smiles feel more melancholic or gentle than happy.
inb4 Zeon actually is the son of Windellant and Aidra but thanks to Kaldus' teaching becomes an even bigger asshole than Kaldus, that would be deliciously ironic storytelling.