*My mum had her assessment.
They are now referring her for a CT scan.
Could take a while but she's going downhill dramatically*.
So sorry to hear that @gingerface40 
There are some practical things that you can do now to help in the future, although you may have done them already.
Ask your DM if you can have POA for both health and financial, if she says yes, apply for it straightaway. Things will be so much easier if you have these.
Apply for Attendance Allowance for her. Useful if she needs any additional help like ready meals, cleaner, gardener or carers.
Ask for a Care Needs Assessment. I'd be there when they come and have an honest think about how much you're willing to take on. The SW will probably be very keen for you to take on things like cooking, shopping, cleaning, laundry, medication. Just bear in mind that anything you do take on is 365 days a year, potentially for years.
Fill in the Herbert Protocol and keep a copy on your phone. It's my experience that they are ok for ages and then suddenly start to wonder. It's a bit of a shock when they do but having this very accessible will help her to be found if she ever does wonder.
Fill in the This is me form and again keep it on your phone. It's useful if she's ever admitted to hospital as you can then email it to the ward who will probably be only too happy to have it from you as it will give them a better idea of how to look after your DM.
Have a look at the Elderly Parents Section as well. There are some very experienced MNers in there 