The Dark Nest Trilogy by Troy Denning
When the ancient insectoid Killiks re-emerge in the Unknown Regions after the Yuuzhan Vong war, the Galactic Alliance, the Jedi, and the Chiss empire are drawn into a complex and multi-sided war. Several young Jedi Knights are absorbed into the Killik hive mind, while Luke and Leia discover previously unknown information about their mother, Padmé Amidala.
Buy from Amazon:
The Joiner King
The Unseen Queen
The Swarm War
This is a post-Return of the Jedi series from the Legends timeline. Think of it as an alternate universe from the sequel movies and newer books.