Raising a Churchless Child

A parent is quoted saying:

As an intelligent human being, it’s her job to find the belief system that is right for her and makes her feel happy and fulfilled.  If she has a burning desire to become a Catholic or a Wiccan or whatever floats her spiritual boat, I’m behind her.

And the encouragement to be moral is:

Do it because it’s right, not because you fear retribution or judgment.

I am uncertain how happiness can decide the fate of ones life so strongly, considering happiness is often so subjective. What if the daughter decided on being a cannibal who murdered her food. As long as she was happy doing this, working 9-5 in her city job, married, serving the neighbours limb to the kids for dinner this would make the mum proud as punch: “At least she is happy”.

Obviously we want objectivity, correct? How do we have objective morality when we believe in no objective moral giver, namely God, who cares about right and wrong, is just and will bring to account the wrongs that have occurred in our lives?