Originally Posted by "IHLACS"
I guess the reason why I'm writing about all this is in wondering if anyone has experienced this type of increasing dysfunction and how the cope with it, deal with it, etc.

Well..

Originally Posted by "IHLACS"
So XW went to dry erase the crayon off the window, which is a good method, (I tell her this.) but leaves a film still. I use lighter fluid or goof off to remove stuff like that because it works even better, and doesn't leave any residue behind.

Oof. Unsolicited advice.

Originally Posted by "IHLACS"
Although a short instance, XW proceeded to argue with me about how her method was better, and that mine uses chemicals

She prefers her way--your is more comprehensive, hers is more green.

Originally Posted by "IHLACS"
I politely explain..

Oof! Mainsplaining.

ICLACS, I think this was unnecessary. First, you could skip offering unsolicited advice. Second, when she disagrees, you could prefer listening, validating, and being curious to "explaining" your view. Even when you must explain your view, considering their view first often makes others more receptive.