I think he's singing about a girl he once loved. It didn't really worked out because they're too different to hold on to this relationship. But in some way, she's a very lonely person, maybe addicted to drugs and she needs someone to take care of her but nobody's there. So he feels guilty because he just can't stop loving her, even if they aren't together anymore so he feels responsible and wants to protect her. She's kind of afraid when the night comes, while he loves the darkness. It could be like a metaphor for the sun and the moon, they love each other and one thing can't exist without the other, but they could never have a relationship.
I think he's singing about a girl he once loved. It didn't really worked out because they're too different to hold on to this relationship. But in some way, she's a very lonely person, maybe addicted to drugs and she needs someone to take care of her but nobody's there. So he feels guilty because he just can't stop loving her, even if they aren't together anymore so he feels responsible and wants to protect her. She's kind of afraid when the night comes, while he loves the darkness. It could be like a metaphor for the sun and the moon, they love each other and one thing can't exist without the other, but they could never have a relationship.