Kikyo is NOT helping Naraku that I know of. When she takes Inuyasha's shards from Kagome and gives them Naraku she explains herself to Inuyasha in the episode where the tetsusaiga is broken. She has a plan that if Naraku collects all the shards first she'll try to cast him and the jewel into oblivion.
PS- The shards that kagome has are not hers they are Inuyasha's because he all the fighting for them.
Submitted by PKIS