Lukvance, I think you have it exactly right: gods exist in the same way that love exists. Love is a real emotion, scientists have located the places in the brain that are activated when someone is in love, and are even beginning to figure out who falls in love with who.Good. That closes the thread God exist (as much as love)
Love exists, this is true! Love is a chemical reaction, but like everything else in your personality it can be changed by proper administration of chemicals or surgically modifying the brain.
If there were truely a soul wouldn't it be impossible to physically change the essense of your being?
Injury to the frontal lobe of the brain can take a god loving / fearing bible thumper and make them a child rapist, atheist.
That means your essence is your physical being a completely biochemical process. Love is an addiction caused by the release of endorphines, while in the presence of someone you have been trained by life to release these chemicals.
In all likelihood I could make you an atheist, amoral, murderer given enough time training, surgery, chemicals and knowledge of the human mind. No magic required.
A better question with a morally ambiguous question like "would you kill your kids if god demanded it" would be what if this was a test not of your faith and loyalty but a test of your morals in the face of an ambiguous task.