When the Dementia person says "thank you".
Caregiving for my mother for that last 1.5 years is the hardest thing I have done (juggling with full-time job, husband, and my life what we have left of it).
Though this morning when I was making breakfast for my 96-yr old mom and she asked how she got to our house (for millionth time), I took a deep breath, gave the abbreviated version what transpired over the last 2 plus years and how we got her from not being able to sit up on her own or to walk to standing and being able to wash and dry her hands and using a walker to get from her wheel chair to the bathroom or to sit outside on the deck and return to her chair.)
She teared up and said, "Thank you." You were always good to me.
That's when I am happy she is here and not in a NH. I know then in the end, I will miss her like crazy and will probably remember the non-dementia mom, but will be satisfied that we helped her to the best of our ability, that she was happy and in familiar surroundings, with family and loved until God has her in his Home.