It comes down to this: are you willing to continue picking up after them, or are you willing to put your foot down and follow through? Doesn't seem like you want to be a maid to extra bodies who are perfectly capable of carrying their own load in your house, so I suggest you and your husband discuss how best to confront, lay boundaries and the consequences, together, as a united front. Then they will know exactly what is expected of them, if they are going to have the privilege of living in your house. I mean, if they lived anywhere else, there would be a lease, right? Very specific rules they'd have to abide or be evicted? It wouldn't be unreasonable for you to lay down the same thing.
And honestly, one of my consequences, if you can't wait out the mounting mess, would be 'if you're going to treat me like a maid, then you're going to PAY for my services.' Get quotes for what it would cost to get all their laundry done, to have the dishes washed, etc. THAT should be a nice eye-opener.
But you have to be firm, whatever your choice of response to this blatant disrespect they are dishing out to you. Because if you're going to cave (and your husband HAS to support you 100%!), then you're going to continue to do everything for these knuckleheads.
Good luck!