Is diagnosis of dementia a good thing

You need an official diagnosis in order to access things like Carer's Allowance. Attendance Allowance, Reduction in Council Tax. Also required to qualify for a Blue Badge. There is no cure for Dementia but medication that may slow down the progress, or alleviate some symptoms (e.g. Anxiety) will only be prescribed once there is a formal diagnosis. There is no need to make a big deal of this with your Mum, who will soon forget the diagnosis as the dementia advances.

As always, please access the Alzheimer Society's web site and Talking Point Forum for support and professional information and advice. In spite of their name they encompass all varieties of Dementia.

You have a long, hard journey ahead and will need all the information/support and advice you can muster.

Sorry to hear that. First of all, yes it’s important to know and read up on it because your Mum will develop different behaviours and medical problems as she progresses through it. Knowing and researching in advance will forewarn you of what to expect and to know not to blame your Mum for acting in ways you find strange, upsetting or aggressive - it’s a cruel disease.
Eventually your Mum won’t manage her financial affairs and will need a Power of Attorney to do it all for her. This should be applied for while she understands and can sign. Otherwise things could become very difficult for you. She should also make a living will too which will mention her end of life wishes etc.
Think about whether you can care for her or whether her medical needs will require nursing home care.
There is a whole host of things to consider with a diagnosis of dementia. Good luck.

There are advantages to having a diagnosis as it is a trigger for certain things to be set in motion.
You would be able to access the memory clinic so drugs to slow the process can be prescribed.
They do help at the start.
You will have a Mental Health nurse assigned ,if you are lucky, who you can discuss things with and can help as things arise which you are not expecting and need help with.
If two people live in the house a diagnosis can get a reduction in Council tax.
As things progress which sadly they will, you can access incontinence products free of charge .
It will only help I believe.