In terms of day-to-day interactions, the best pieces of advice I received was to:
* redirect the conversation rather than argue or correct them.
* always flash a look like you just recognized them and are happy to see them before approaching.
* don't ask them if they remember something. They don't and will just rationalize a scenario in which you are antagonizing them. * don't watch action/war movies with them around.
* don't inform or remind them of their condition. It just makes them sad for a bit and they'll forget anyway.
* ask them about distant childhood memories and play them their favorite music.
I hate to end on this, but this isn't a condition that gets better. There were good days and bad days and they eventually all became bad days. Spend time with your loved one and try to get as many of those good times as you can now.