AAARRRGHHH! My fiance NEVER sorts clothes, and he washes them all on warm. Everything is gray, or pink, with fuzzballs on it cause he washes them all on heavy duty. He may as well beat them on a rock at the riverside.
And I love my stepsons, I really do. But they are gross (skidmarks) and I don't want my or my daughter's pretty clothes washed with a bunch of dirty nasty boy clothes. I wash the girl and boy things separately. He doesn't. I hate finding my shrunken, shot elastic bra (from being dried on high heat) tangled around a pair of yellowing used-to-be tighty whities from some 8 year old that still hasn't gotten the knack of wiping his ass.

But I think the stupidest argument we ever had came before we moved in together. I had washed his bedclothes at his apartment, and put them in the dryer, but I had to leave before I could make the bed. So I told him they were in the dryer, and left. The next day, I ask him "Did you make the bed up?"

him: Oh yeah!

So I get over to the house later, only to find that he slept on the couch that night and did NOT make the bed. What makes this a dumb argument is WHO LIES ABOUT MAKING THE BED?! Really, who does that? I was like "What are you, 5 years old? All you had to say was 'No, not yet'. For chrissakes, I was on my way over! I was bound to find out! If you'll lie to me about something this inconsequential, what else are you lying about?!?!"

He's sitting about 3 feet from me playing GTA on his pc. I think I'll go punch him in the head now that I've remembered that argument from over a year ago.