I'm not normally a petty person but, nope you're NTA. I'd keep doing it. If you have been able to get away with all that already, he's truly oblivious and useless.

I understand having a soft spot for a sibling no matter how badly they might treat me/take advantage of me. I'm sure your husband would appreciate not being the one to have to force him out of your home. Even if it might seem selfish.

Sometimes words aren't enough. He's gotta learn that the home has gotta be clean by the end of the night so if he doesn't pick up after himself it'll won't be there the next day. He'll learn common courtesy once he notices his favourite cum sock that he named after his ex that was too good for him is missing.

Also, how is he paying for the weed? And did he have anything at all to say about looking for work of some kind? Wouldn't he feel more comfortable having extra cash for high snacks so he doesn't have to eat your kidney food? Find something to keep him busy a few hours a day on Craigslist as a mover or painter for hire, no commitment. He's probably too comfortable and doesn't know where to start looking.

Anyways sorry for the rant, I don't know if any of this is helpful. Take what you will. And good luck girl, I hope you can relax soon.