[legion]

There is no tactful way that will result in her changing her behavior. You've been tactful so far. Where has that got you?

You have to decide if it is more important to you to have her change her behavior or that she not get mad at you, because you can't have both. Women (and yes, I'm generalizing) seem to get very upset when you suggest they are anything less than the definition of perfection. I think it's an insecurity thing.

You could at least start to act pretty irritated the next time she does this. You could start deducting the car repair expenses from other things. (Like the vacation fund.) You could explain to her that getting an alignment every 3 months is not normal. (I get one every 3 years, and I think I'm anal about that kind of stuff.)