The true nature of Shiva and Shakthi is not a heavenly couple with human attributes. Their nature is not a human family with children. The mythological story is not wrong, but it is a metaphor for a far deeper and subtle concept that needs to be understood.
When we look at Kali and Parvati, they are representations of "Shakthi". What exactly would that mean? Shiva and Parvati – Ardhanarishwara is complete consciousness. What does this mean?
Here is an attempt to explain a very subtle but simple point which appears complex because of our nature of understanding. We simply don’t understand simple things :).
Am talking about a "constant" and its apparent nature through its manifestation. Shiva represents the unchanging nature, Shakthi represents the changing nature. We relate to the Shakthi part because it communicates with us, through action/thought/senses all of which are manifestations, making it appear as if that defines our nature when the real truth is that the unchanging nature inside is the true nature we possess, also known as Shiva.
In terms of Kundalini, there are states of Shiva at each chakra but what really matters is the Shiva at the Sahasrara Chakra. Kundalini rises, Shiva doesn't move. Kundalini manifests in change of nature during the ascent, while Shiva is the constant at the pinnacle.
I have an even simpler, easily comprehendible, more relatable version to explain this concept.
Lets look at a Circle. Its nature is defined by πr2 where π is the constant and r2 is the variable. Let's examine this point.
In the equation that defines the physical attributes of an entity we call a circle, A=πr2
Let’s break this down to its various pieces.
Circle - I define this as consciousness in abstraction
A - I define this as the consciousness now manifested in a form with a physical presence - Area.
π - I take this as the constant which has always been there and will continue to be there and that makes a circle manifest in the form that it took up. It is beyond the realm of time and space.
r2 - I take this as the ever changing nature of the circle where r is the variable. This is needed for π to manifest itself.
A combination of these concepts gives the circle its living presence in our manifested world.
In human terms I am defining myself as A - which is my manifested form in this world with a name that you identify with. While you associate with A, you discover r2 - which is my ever changing nature that defines my outward character which is temperamental and is not the real thing. But you don’t know my truth which is the same as yours and that is π, which is the subtle constant, our individual consciousness. But in all abstraction, my consciousness and yours is the circle that we never realized is our actual truth.
The sacred scriptures seem to reiterate the same concept. It is the "Shakthi" within us that makes us manifest in different forms as different people but the core truth is that you and I are actually Shiva, we are the same in abstraction and it’s in our inherent nature after being born human to find it and identify with it.