These are basically the anime songs I listen to if I want to sleep... These are just soothing, and I like how they lull me to forget about my problems and just choose to sleep LoL. (I've already recommended the first one before, but I think it's worth mentioning again because it really fits with the theme!)
Life Is Like A Boat (Bleach):
Hoshiboshi No Uta (Fairy Tail):
Kansha (Bleach):