Hello Shoey
OK, take a deep breath & stop panicking. (Not being insulting, that's what most of us feel at first!) Yes, it's a bloody awful disease, no-one deserves it.
Perhaps you could tell us a bit about your family; how old is your father (& Mum, & you come to that) what's his behaviour like, has he been prescribed any medication? Do you live with them, or nearby, or some distance away? Does he have any physical problems at the moment, or is it mainly memory loss and the confusions which that can cause?
The way most of us cope is 'day-by-day'. Deal with the immediate problems as best you can (or find out how to help Mum cope with them) & don't try to look too far ahead and imagine what "might" happen in the future. It might not, and you will have wasted energy & suffered more heartache for nothing.
If you look right at the top left hand corner of the Talking Point pages, you'll see a link button "i Factsheets". These are produced by the Alzheimer's Society and contain a HUGE amount of information. You can learn a lot from them, and help your Mum cope that way; or point her at them if she can find time to use the computer.
That's a starting point anyway - post again with specific questions as & whenever you have them. Break the difficulties down into smaller chunks which are easier to get your head around. Small steps ...
Best wishes