One of the blogs that I subscribe to is called Mother Tongue Annoyances. It's written by a New Yorker that loves the English language and investigating its proper and improper usages. He's moved down to Tennessee as an adult and, thus, has plenty of examples of improper usage to complain about. Occasionally, he'll write a post that isn't really on the general topic of the blog, but more of a personal pondering. Yesterday's was such a post, when he tackled the not-so-simple subject of Fate vs. Free Will in a post he called, If It Is Meant To Be...
The only reason I'm writing about it is that I left possibly the best comment I've ever left on a blog on that post, and I felt that I must save this gem of reason here for posterity. Obviously, you should read his post first to give it the most context.
"Mom, if you believe that our lives are preordained, then exactly who is doing the ordaining?"
Your fallacy here, ironically, is in your use of the anthropomorphic verb "to ordain". "No one" is a perfectly valid response to that. Do you seek an anthropomorphic reason for gravity or why 2+2=4? No. It just is that way.
Some think that the apparent passage of time is merely an illusion in our perception, and that the future is just as fixed in existence as the past. But speaking in those terms accomplishes nothing. Since we live in this perceived temporal world, it's pointless to speak about it otherwise.
Even people that claim to be fatalists don't really believe that they have no free will. They still make plans for the future and go to work and decide what to do on the weekends. It's because humans can't function any other way.
What your mother is doing is rationalizing situations by claiming innocence from lack of control. While helpful in avoiding depression from over-self-blame, it can be a dangerous attitude when you need motivation to "try, try again".
Religions have formed as they have because of the wiring in the human brain, and the evolutionary advantages of attributing unexplained events to an external, thinking agent. This predisposition to anthropomorphize the unknown is very, very present in our vocabulary and language. Being aware of the intrinsic bias towards religion in our words is very important when talking about these philosophical matters in an objective way.
It's rare for me to have such a moment of Dawkins-like clarity and be able to articulate it so well. The comment even brought the topic back onto the general topic of his blog.
I apologize for my lack of humility here, but that last paragraph is just gorgeous!