My Mom has that ability to "turn on a switch" when she is around friends. How can I encourage her to flip that switch on around us?

Like others who have posted about this condition, my mom (who is in the early stage of dementia) can appear to be almost "dementia free" when she is around her good friends-either when they come to visit or when she goes out to eat with them. She has always enjoyed spending time with friends and I'm grateful that she still does. The thing is, her behavior is so "night and day" from how she acts with me and my family (we are her caregivers) compared to being with her friends, that it's frustrating she can do basic tasks on her own when I'm not around, but when I am she cannot do anything without being prompted, several times usually. When I suggest that she can try to do something, she says that I'm out of my mind if I think she can do "such and such" (for instance, hang up the phone). Another aspect is that her friends will say things like "Oh you should really take your mom on a vacation" or "Your mom told me that she never gets to go for walks" which I would like to reply "You have no idea how she is when you leave!" Getting her to take a walk is always iffy, going on a vacation would cause her so much apprehension that we'd look forward to coming home to recuperate; even motivating her to get out of bed to get ready to go somewhere with us or with her friends is usually a battle as well...her well meaning friends have no idea of the reality.

It's been about a year since we've moved in to help her, and I try to focus on the good things: mom can still live in her home, my loving husband was not only willing to make the move but actually initiated it, the move has helped my MIL to move into our house with her cousin for companionship, I can help my mom with things she needs done for her (cooking, cleaning, laundry, verbal cues for shower/clothes etc., exercising and walking with her, finding things she loses-I tried to have her help a couple of times and it wasn't worth her frustration)- and I can still spend quality time with my daughter. Looking at the big picture and comparing this to the problems others have posted about I see I'm being short-sighted. I would still, however, greatly appreciate any advice or input. Thanks in advance.