Why do some people see happiness, and try to tear it to the ground?

Because they want others to stoop as low as they feel. Makes them feel like they have company. Misery loves company.

We are all life-energy, and if we are conflicted with, our polar natures of light and dark, we will constantly experience a feeling of “backlash”. For example, when you are opposed to the dark-nature, you will feel a backlash from it, and when you are opposed to the light-nature, you will subsequently feel its backlash also.

If they are miserable, they want other people to be miserable too.

I'm self destructive so that must be it

because they are bellends