Selene is easy to deal with. Target a mob and hit 'Obey' and she won't use anything until told, while still spamming Embrace on whoever needs it.
It's Eos where you have to put her back in steady, but if you need her to use Whispering Dawn then you proberbly need her other skills too. Rouse > Fey Illumination, (takes Eos out of steady) Auto Whispering Dawn with +40% and +20% healing.
As above, if you target a mob and hit obey she won't do that anymore.