Joliette, I can't help but wonder if your mother knows much about atheists. Especially since the WTS doesn't pass on much in the way of real information about us. Even if you told her about it--I'm guessing you're an atheist yourself?--would she even hear it? I doubt she'd really listen or absorb very much of it.
Of course, if she wants to tell you all about her beliefs, I'm sure you're supposed to listen devotedly or else? I have a legion of in-laws who can be the same way.
I'd be fascinated to see her prove that the laws she thinks came from God actually did, instead of just the WTS or even just the minds of the Bible's human authors. But that's just me being silly. Her 2 places to start: prove the Bible is truly God's unaltered Word and that the GB was really appointed by Jesus to rule his Earthly org. Only then can she assert her beliefs to be true about anyone elses.
Anyway, best of luck my friend. I may have JW in-laws, but at least my parents aren't JWs. That ain't fun for none of us, I think.