They say it takes 26 days to create a NEW habit, changing it from an old one.
Right now, your muscles and subconscious remember to put your hand where it is now (which really isn't that bad. Possibly a little high, but if she's making nice runs....). You've got to re-train your muscles and brain to hold your hand lower.
That means you're going to have to actually and actively think about it during your runs, and especially during practicing. Until it become automatic.