Lila watched the demon wretch, emptying his stomach. It was a sorry sight to see but one she could sympathize with. Sometimes, people take others for granted not because they are unappreciative but because they get comfortable.
At other times, it's due to ignorance that one's efforts go unrewarded. This was the case with Magnus. His mate had no idea what each vision took from him. Although he was immortal, he could still feel pain every time.
He could still bleed and get hurt. She helped Cosmo understand why Magnus would treasure it. Unlike the rest of the world, she could relate to his pain. She understood him in a way that no one else could.
Additionally, when they are together, the two can easily take away each other's pain or share it. She gave Cosmo time to pull himself together.