tl;dr: We use concepts to make sense of the world. The raw reality, however, is empty, constantly changing, and deeply interconnected. These realizations can give rise to profound feelings of stability and safety to rest in.
Epistemic state: This post is quite "out there", a realm I do enjoy exploring. While some points seem very true to me, I am also in many ways uncertain about this at my current stage. Mainly synthesized from various Buddhist and mental health sources, largely Waking up, Tara Brach, and Being Well, next to other sources and my own experiences.
We never experience things outside of us directly. Instead, what we perceive are projections of whatever configuration of matter and energy exists in objective reality. Photons and sound waves travel to our senses, transmitting signals about their origin. We sense only a mirror image of the "outside". And then we try to make sense of these sensations, which means we develop models (call them concepts, beliefs, thoughts, forms, abstractions, theories, narratives, stories, etc.) to understand and predict our sensory experience based on its emergent patterns. Our subjective experience on a conceptual level, that is, the way we understand and explain what happens, is an internal simulation in the brain of what probably happens outside of us based on the input we receive. That means our models are not the same as the things in objective reality they seek to conceptualize. The map is not the territory. And that, in turn, means we can modify our map, exchange our beliefs dependent on the situation, or create new theories. This makes thinking a very powerful tool, because nothing lasts forever and we constantly need to adapt to new circumstances. It is particularly helpful in the social context, where we might want to maintain group identities and follow their rules. Note that the "sensations" we are making sense of includes anything that appears in awareness, including internal experiences we might receive from the body.
The interesting thing is that we can also lay this tool down — including the concept for the one who observes, known as the "self" or the "I" — and just witness the raw sensations as they are, without judging nor analyzing them. Allowing the controlling thinking mind to unclench and quieten, this total dissolution of all concepts (aka emptiness) is an incredibly liberating experience, because it not only shows how flexible subjective reality actually is (and gives the mind a well-deserved pause), but it also readily gives access to everything that truly matters — like safety, stability, love, fulfillment, aliveness, wholeness — already available within. Some might find the idea of a malleable reality scary, and that's okay. Most of us are socialized from early on that we (our thinking minds) must know and control at all times, and it is very hard to let go of such deeply ingrained beliefs, very easy to find reasons why we shouldn't. And yet, paradoxically, no circumstance can provide a stronger feeling of stability than the constancy of the pure awareness itself (the background where sensations appear), because everything else, including the self, is unavoidably changing.
This relentless change (aka impermanence), however, isn't totally random. Instead, the Universe continues to increase entropy. We are phenomena in the Universe appearing as part of this inevitable change. In a sense, we are change. Our brains have evolved as part of this change to convert free energy into better choices, into sustaining life. And the desire to sustain life, the desire for the system of life to be well and flourish, is more commonly known as compassion. Thus, everything a human does is, at least on a fundamental level, already an act of compassion. (This is not to say that it necessarily feels like compassion, in a social sense, nor that every action actually has a helpful impact, of course. Life is complex and humans very limited, so some protective actions may be maladaptive or dysfunctional, potentially leading to quite harmful outcomes, which might need external help for transformation and accountability.)
Really digesting this is liberating in many ways. Firstly, things just happen. Time moves on. There is no action without prior causes, no stop button to reject what's already happening and try over again. Even death is just another change in the Universe (though it can be an important one). All doing, all thoughts and goals are just appearances in pure awareness. All experiences are, eventually, just a matter of luck. This lack of control might be scary, and that's okay. There is no point in resisting constant change, expecting and forcing things to be different than they already are. It's futile, even a harmful delusion, to seek identity in the past or safety in the future, in an ever-changing reality. We can equally let go of all that constant resistance, of impossible expectations, and fruitless forcing. This allows to relax, to experience life fully as it is right now, and to connect deeply with those around us. It's the middle way: Neither totally believing or clinging to anything particular (not) being real or true, nor totally dismissing or separating from any existence; neither total integration nor total differentiation. Instead, be with life. Secondly, everyone deeply wants good. Seemly "bad" thoughts and emotions are actually attempts to protect the system, calling on us to forgive and embrace them, to thank and honor their efforts, and to reflect with them on better, often more adaptive strategies for what they actually want. Only if we accept and hear them for what they are, they can change. As a consequence, we can live with integrity, reach beyond concepts that divide us, and unite to wisely address the local and global challenges we are currently facing. And finally, we are inseparably a part of the Universe. Despite the sense of a separate self we are taught to be, our lives deeply depend on and affect the ecosystems around us: people, animals, plants, water, air, the sun, and so much more. This feeling of interconnectedness with the vast and constantly changing whole provides a profound feeling of belonging and safety, soothing all fears. Everything you encounter, every request you receive, even life itself, is an offer from the Universe, and it is your responsibility, your freedom, to make the best of it and to contribute to awaken compassion in the larger whole.
Like emptiness and the stability that arises from it, interconnectedness and compassion don't need to be created, but to be unveiled, since they are already there. However, most people live in cultures that seem to have forgotten about such fundamental insights. Thus, the journey to experience them first-hand in a deep, visceral way can be long and painful. And yet, they are right under the surface. You just have to look :)