I have written before on how there is a fundamental restlessness at the heart of our being, or a fundamental loneliness, as some writers like to call it. Many are the strategies we use to get away from this, such as over-working,  continually running, throwing ourselves into relationships. staying constantly distracted.   And when those things are working for us, loneliness  does indeed seem absent. However, what we come to see over time is that is that this loneliness, or restlessness,  is something essential to human nature; we may succeed in covering it over for a while but it  can never actually go away.  As we can see in these two quotes from different sources, most wisdom traditions say the same thing: this feeling of restlessness, of having no real ground to stand on,  is part of being human, because there is nothing in existence that can completely fill the human heart. And at the end of the day this shows us the core of our practice, nothing other than learning to stay.

There is a deep hole in your being, like an abyss. You will never succeed in filling that hole, because your needs are inexhaustible. You have to work around it so that gradually the abyss closes.

Since the hole is so enormous and your anguish so deep, you will always be tempted to flee from it. There are two extremes to avoid: being completely absorbed in your pain and being distracted by so many things that you stay far away from the wound you want to heal.

Henri Nouwen

If we are willing to give up hope that insecurity and pain can be exterminated, then we can have  the courage to relax with the groundlessness of our situation.  This is the first step on the path.

Pema Chodron