"The [human] species will never learn to co-exist if given total freedom."

[Diana]

When you are attached to certain outcomes, there is a kind of a muscle tension and uncomfortableness, which you are not even consciously aware of mostly, you just don't feel at ease or peaceful, and when you let go, the tension just vanishes.

I agree with this. It also aligns with the wave/particle duality, where the particle function allows for one outcome (attachment to outcome; control), and the wave function allows for all possible outcomes (freedom; possibilities).

For me it's faith, it's letting go.

These are two different concepts. What is it you have faith in? Having faith is attachment to a belief that all is well or that things will come out "right," it is not letting go. Faith is a kind of displaced control, onto some force (OIC, God, the Universe) that is in control. Faith infers an emotional charge; there is no emotional charge in detachment.

Acceptance is freedom. It's knowing that all is well.

Again, two different concepts. Letting go of control, acceptance, detachment, does not mean all is well. One might accept a war of human construct killing and maiming people, animals, plant life, etc., but one does not have to think or believe it is "well." One can still dislike suffering—or let's say not align with suffering—but accept it as the way this realm operates at this point in time for whatever reasons.