Perhaps I should explain what I meant by object constancy. It refers to how a narcissist cannot understand that one object can have good and bad qualities at the same time. That's why they idealize or demonize you instead of having an accurate idea of a your real qualities. When I first read this, so many things im my life made sense.

The narcissist in my family is quick to denounce things at the first hitch. If you offend her once, she forgets every nice thing you ever did. If one part of the house needs maintenance, she declares the entire house a piece of junk and talks about burning it down even though we don't have anywhere else to live. She will be happy with a new car one day and on the second day say it was a lemon and she was cheated (it's the quick version how they flip flop in their view of personal relationships).

And the way she denounces the garden is because she can't understand that there is a cycle of growth and dormancy, and generations of plants that are born, produce offspring, and die. She cannot understand that there isn't a garden in the world that hasn't had a plant die. To a narcissist 1 failure and 99 successes amount to 100% failure. Just as one flaw in an otherwise good person makes them 100% evil in the narcissist's eyes. I have been trying to grow thicker skin and accept that she cannot see the world accurately or logically and her words mean nothing. She tends to drop the "all our plants are dead" bomb when I'm in a good mood and not expecting it so it catches me off guard and ruins my sense of accomplishment.