I reread The Vampire Lestat and Queen of the Damned for maybe the 3rd time? Likely the last. Lestat was OK. I remember not liking QotD much the first or second times, but I do change over the years so I gave it one more try.
Still don't like it. Probably for different reasons. It's too long and waaaay too long on the topic of morality.
I know the backstory for Interview with a Vampire. It flows into Lestat. I believe most books - most good books, anyway - are therapy books: written by a person working stuff out. People who churn out blockbuster after blockbuster maybe not so much, but many authors write because they have something to say and they are good at saying it in an entertaining fashion.
This author seems to be saying that humankind is evolving toward morality by removing all aspects of the spiritual and doing whatever they want as long as the motivation is love. "Love" is not really defined, although all the vampires seem to have it for their victims even as they rip their heads off and crush their bodies to pulp while drinking all their blood. They also all seem to want to be human again as long as they don't die.
She paints a picture of all these atheists (although even that isn't correct because only the vampires seem to even think about gods) just getting along with each other in cities like Miami and San Francisco and doing their own thing without hurting each other anymore. The vampires discuss how the world keeps evolving into more and more loving of neighbors as religious thought is abandoned.
Obviously a fictional world. Seems pretty clear to me thirty years after publication that removing religious thought from the marketplace leads to insanity, incivility and disorder. The world is searching for a Messiah more than ever. Focusing on presidents or world leaders instead of considering how each person can make a difference in their own tiny sphere of influence. Enough people living in the light daily would transform the world. Russell Brand has the correct idea there.
Morality is found in God but it does have to be lived to make a difference in the world. It's not a thing that is stumbled into. Not yet.
Keep the faith.