New here - How can we make this situation easier?

Hey guys.

Was just looking for any advice you might have to help me and my boyfriend and his dad who seems to have dementia.

We don't have a diagnosis yet, we're waiting for an appointment at a memory clinic after being referred from the GP. We're in the UK but there are big waiting times, though we have just found out his dad has private health insurance so hoping to get in sooner.

Anyway, basically the dad can't seem to do much himself. He's ended up staying at my boyfriend's house and I'm wondering how long this is going to go on for. My boyfriend's brother seems to have shirked responsibility onto my boyfriend basically. The dad is very slow and definitely getting very frail, despite being a fairly fit 70 yr old. He is always losing stuff, has had some hallucinations, won't drink water. My bf cooks him lunch and dinner as he can't seem to do that. Thankfully he is still washing and going to the loo himself, though has difficulty dressing (t-shirts inside out sorta thing). He has tried going out for walks by himself but immediately gets lost. He gets lost in my bf's two bed flat and has a tendency to wander into my bf's room. I put signs up to try and help but still does it - the dad fell asleep in my bfs bed a few nights ago and then wandered in to his bedroom twice last night at 3am. He is also very paranoid and resistant to anything, insisting he wants to buy a 6 bed house near to my bf, once he's sold his old house. He is constantly with us and we're not getting much time alone. We are thinking it is probably dementia, and after talking to a friend of mine who is a doctor she reckons it is too. Obviously not 100% certain though.

My bf suggested getting carers (though worded as friends), more to give him a hand, but his dad was very much unimpressed. My bf then suggested maybe the 6 bed house wasn't the best idea if he gets lost at his. He got a bit annoyed and then started going on about the doctors going after him and how they are in a conspiracy theory. He is also terrified of being put in a home. My bf and his brother doesn't have POA and is scared to even bring it up now while his dad is so paranoid.

I don't know what to do but I'm scared. I don't know how to make this any easier and how to get any time to ourselves! Especially as I know this is a long, drawn out disease - is this gonna be us for the next 4+ years? Just getting worse and worse?

I'm hoping his brother might help a bit but I don't know how likely it is. His brother insists him and the dad don't get on at all and he also has a kid so can't do as much. His wife seems a bit more understanding but idk how likely it is. There's also talk of the dad staying at his own brothers, but there is worry that we're shifting him about a lot.

Is there any way of trying to get his dad on board with carers on the house? Or are we just going to have to put up with him until his dad is seriously ill? Will it be any easier after a diagnosis? I am imagining his dad to be resistant to the bitter end at this stage. I am scared of how on earth we will ever get time to ourselves. If anyone has any tips or advice on making this any easier, please let me know. And also how to communicate to resistant parents!

Thank you so much!