As part of our series into chronic conditions across Wales, the BBC news website profiles life with Alzheimer's disease.
Trish Davies' two daughters help to look after her
Alzheimer's is one of the most common forms of dementia, with the main symptom being loss of memory.
It is a progressive illness and can be distressing and disabling.
The Davies family, from Nantyglo near Brynmawr, were rocked eight years ago when mother Trish was diagnosed with Alzheimer's disease at the age of 35.
Now 43, Mrs Davies said in the months before the diagnosis, she had been getting severe headaches and pains and that she used to forget simple things.
"They put it down to sleep deprivation and depression but I have been depressed before and it didn't feel the same," she said.
"To be perfectly honest, I thought I had a brain tumour - and there is epilepsy in the family - I thought I might be having fits in my sleep."
Her husband Kelvin, 57, said he had started noticing that his wife failed to keep up with anything new and began watching old episodes of shows that had been very familiar to her.
The family use a diary to keep a regular routine
"It was not my wife at all - she wasn't behaving normally," he said.
He said it took three years to get a diagnosis, after an MRI scan revealed she had suffered a series of minor strokes. The couple were told that Mrs Davies "could die today or live for another 15 years".
"I think there were problems with doctors accepting that someone that young could have dementia," he added.
Daughter Chamelle said that she and her sister Jadee-Lee had noticed their mother seemed to be "forgetting quite a lot".
"She used to do a lot of singing, but her mind started blanking out, and she would get a bit angry, but it was at herself as she didn't know what was happening."
When the diagnosis came, Mrs Davies said that it had not made an immediate impact to her.
"My symptoms didn't change, but it is nice it has a name and that I wasn't going mad," she said.
"I think I used to get angry with Kelvin - I was so frustrated, I didn't know what was going on."
She said the condition was different for than it was for her family who are constantly aware of what is happening.
"I am not aware half the time I am ill, I don't see anything different," she said.
"But, I think we were always a close family and we are closer still."
Mr Davies said it had completely changed his life.
"I am a full-time carer - I am like a domestic mum and I am dad to two kids. I run the house and all the day-to-day stuff."
"It is hard at times. We have a very strong relationship - my wife is my soul-mate and there is plenty of laughter.
"I see her getting frustrated - she can forget what she is saying. It can be like a child taking a first step, but you know she isn't going to get any better.
"It can be emotionally draining but it is not like that for 24 hours."
"Sometimes, we have a normal conversation, but an hour later, that conversation had never taken place - she would say we haven't spoken about it."
He added that his wife's condition appears to move in stages.
"She can move along steadily, but might overnight have a minor stroke and take a step down, but then there is a plateau, but a bit lower than she was before."
He said the couple had been very honest with his wife's two children from a previous relationship.
In their bid to keep their life organised, the family now use a special diary that they use "for everything".
"We try and go out visiting some of the family - it is very organised. We keep to routines," said Mr Davies.
He said the Alzheimer's Society had helped with the diagnosis and was grateful to the organisation Crossroads, who visit on Wednesdays to give him some free time.