Hi David
it can be difficult, but try not to pre-judge. sometimes things can work out, but best to be prepared either way.
My Jan [originally from Neath] tried a day centre [in Hampshire]when she was your wife's age.
Sylvia speaks wisely, try the 'helping the older folks' line if you need to. It worked briefly for Jan - 1 visit actually - but each person is different from any other, so it may work longer for your wife.
In the place we tried, there was a load of older people - mostly women. They were in their late 70s and 80s. Jan wondered what the heck was going on. She wasn't into throwing fluffy balls around. The first visit I stayed the whole time with her, hoping she might settle. On the other 2 visits I sneaked out while the staff diverted her attention, and spent the duration unable to do anything at all, just fretting about her and feeling guilty.
After 3 visits we were banned anyway because Jan, being a young onset person, was so mad at being stuffed in with so many old people that she simply ran amok.
We also tried the local Alzheimer's Society centre. That also was okay as long as I sat alongside her and held her hand all of the time. Which was not quite the idea.
Your wife is very positive and that is good. Just treat it all as if it is perfectly normal, and judge the situation as it happens. It might work well for you - I certainly hope so.