Alcoholic uncle with possible dementia - at my wit's end. Any suggestions?

I feel like I'm in a bit of a different situation than many I have read on this forum. A little background: I live with my husband and his uncle, in the uncle's house. The uncle has been a severe alcoholic for years. The rest of my husband's family gave up on the uncle ages ago. My husband and I found ourselves in dire straits and needed somewhere to stay, so we moved in with the uncle to rent a couple rooms in his large house. We've lived here for about 9 years. When we first moved in, the uncle was frustrating because of his alcoholism, but in the past couple years especially he has taken a turn for the worst and we strongly suspect dementia. The uncle and I have never gotten along, but for the most part we leave each other alone and that works for us. But lately he has become extremely forgetful and demanding of my husband. We moved in with the verbal agreement (our mistake, we should have put something in writing) that we would pay a certain amount in rent and nothing else. But the uncle started to forget to pay the utility bills and every month we'd find the water was off, or suddenly we'd have our power cut off; so my husband, who had a very well paying job at the time, took over the bills just because it was more convenient. Sadly, my husband was laid off about a year ago. The uncle has deteriorated significantly since then. Now not a day goes by that he doesn't call my husband to b*** to him about how we're behind on rent - this is true. But we're behind on rent because we've been paying ALL the utilities. Uncle insists that the agreement was that we'd pay rent and all utilities. Won't hear otherwise. He berates my husband nastily about how he needs to cut his hair and shave his beard because 'nobody will hire you when you look like sh**. This riles me up something fierce; my husband looks FINE. Husband just nods, says okay, agrees, until uncle gives up and goes back into his room. Husband does this because uncle won't remember any of it in an hour or two. He can let it go. I can't. Uncle has left the kitchen in complete horrible mess, and I refuse to clean it. At first, he didn't understand why I wasn't cleaning his house, because 'when I was coming up, that's what women did'. Sorry, I'm not cleaning your entire house when we only rent two rooms of it. I will clean up after me and my husband but not the huge messes you leave in the kitchen. His refrigerator (we have our own because he forgets what food is his and will eat ours) is a damn health hazard. He leaves the stove or toaster on and sets off the smoke alarm and then insists that he never turned them on even though we know he was in the kitchen ten minutes before. he doesn't remember, but he gets nasty when we tell him it was him. He wakes my husband up at 4 am to complain that there are boxes in the basement that aren't broken down. In his mind, unless boxes are broken down, 'the fire marshall will come in here and condemn the place'. Husband goes along with it. Uncle got it into his head that our bathroom doorknob needed to be replaced with one that uses a key. 'I need a key to every door in this house'. (I put my foot down on this one. There is no reason for a bathroom to need a key lock, and I certainly don't want him with a key to the room I shower in.) His justification to me when I refused this: 'what if you died in there and we can't get you?' me: 'then you break the door down.' him: 'I don't want dead people in my house!' He wouldn't let it go until my husband distracted him with some other topic and then he later forgot all about it. He's paranoid. I don't know if this is from the alcoholism or possible dementia or both. insists that all curtains be drawn at all times because 'kids come up and look in' or 'the neighbors will tell me they can see into the house'. Uncle insisted (at 5 am) that my husband take the curtains down to wash them because 'the neighbors will see that the curtains are dirty' (they aren't). Next day blows up at my husband; 'leave my f**king curtains alone!!'. There is no way we can get him to a doctor to see about dementia. We can't force him to do anything. Husband's family is divorced from the uncle's care and needs completely and leaves all this to my husband to handle, for which I am very resentful. Husband is stressed out all the time. We have to be silent when we hear the uncle come out of his room because if he hears us talking, he will call my husband out and talk in circles about curtains, boxes, yard work (all of which he says 'we' need to do, but what happens is my husband does it and uncle 'supervises' while criticizing him the whole time) for HOURS, LITERAL HOURS. I am really struggling, mostly from guilt. I don't love the uncle, but of course my husband does. But my husband needs help his family won't provide. Does this sound like dementia? I know I am wrong for feeling so angry and resentful, but I can't help it. I feel powerless. Any advice is appreciated. Sorry for the long post.