New territory with vascular dementia

Hello! My mom just turned 96. As both my husband and I work full time (and all my siblings are out of the area), we helped mom sell her house two years ago to move to a brand new assisted living community in the same town, 8 minutes from our house. She had cognitive impairment, was forgetting her meds, not paying bills, left a burner on and thankfully didn’t start a fire, let her drivers license lapse and so was becoming socially isolated. She’s quite physically healthy and quite bright! She has done well at her new place, only needing med reminders, but in the last several months repeatedly forgets that her loved ones have passed away (my dad, my brother, her parents and siblings, etc). When she remembers or asks us if they have died, after 20-30 minutes of soothing assurances of the facts she gets it all straight again and is ok (and relieved). However, just recently she got it in her head that since my dad hadn’t “come home” that he must be somewhere having an affair, and of course this was devastating to her. Note: they were married 60 years. 6 kids, devout Catholics, and my dad was the absolute most wonderful, loyal husband, dad and family man. He died 15 years ago. She isn’t at the point where we can tell what I’ve heard is called a “therapeutic fib”; eg: “Dad ran to the store and he’ll be back shortly”. Instead, she understands the truth of the matter once explained, acknowledged that dad would never have cheated on her, and as a result feels she is losing her mind, not understanding why she can’t remember such significant events like my dad and brother passing from cancer or the fact that she constantly thinks my dad just died this week and we need to plan the funeral (until we explain it all for the 100th time and she gets relief from the confusion and anxiety). She is also recently thinking she’s only been at the community for a few days and is blown away when she finds out she’s been there two years. I’m looking for guidance from those with similar stories, wondering what comes next, if there is some kind of consistent timeline at this age, etc. She will be able to transition to the next care level, and then memory care if needed, but we don’t want to bump her “up” until appropriate. She still does everything on her own (bathe, dress, makeup, jewelry, etc., goes to many of the daily activities offered, happy hours, meals in the dining room, etc.) including cleaning the cat box at least half of the time! :-) I’m guessing the next phase will be complete memory loss? When we will then be using the therapeutic lies? Or no? It’s a terrible phase for her and pretty draining for me and the other siblings as she calls with the heartbreaking questions sometimes 2-3 times a day. I know others suffering so much more as caregivers and I salute you, but wanted to share in the chance someone else is experiencing a similar situation, thanks for reading!