God, grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference.
Yes, that is the Serenity Prayer. How true it is.
If you cannot change your world (you can run away from certain circumstances, but not the entire world... nor yourself), then you had better realize that the world and the things that you cannot change will change you. Stress from conflict with our environment will change us if we don't change ourselves.
The addict tries to avoid the change, i.e. tolerate it, by numbing the pain from his breakdown under stress. As the environmental stress wears him down, he uses to escape his suffering. The only problem is that he becomes distorted and does not really tolerate his circumstances.
Tolerable conditions are ones we can resist. Intolerable conditions change us no matter how hard we try to not be changed.
So, you have a choice: either leave, or learn to steer the stress in such a way that you can come away better for it.
For example, if you are unjustly imprisoned, there is nothing you can do about it. The stress will destroy you, up until you realize that you cannot change the walls or the guards, and must work on yourself. Successful prisoners do this and become amazing people because they stop trying to make the intolerable conditions of pointless prison torture and confinement into tolerable ones, and so the intolerable conditions become opportunities for spiritual and personal growth. They accept that prison is intolerable and that they will be changed by the experience.
Then they go about guiding the change.
It is like a rough piece of metal being forced into a grinding wheel. If you cannot avoid being pushed into the wheel, what you can do is turn it this way and that and control the places where the wheel grinds, so that then the force finally subsides, the metal is evenly and smoothly shaped. However, if you refuse to move the metal, all you get is a big flat spot and a lot of heat because, so long as the metal is moving, the wheel actually touches only the raised spots on the metal.
There are changes you cannot avoid, and there are many situations in life that are supposed to be intolerable. That is because humans are designed to change. We are made to grow and grow and grow. For us, to be without growth is an intolerable condition, and that is how many people become addicts, because the addiction helps temporarily endure the pain of not growing. We cannot tolerate our own needs to grow and change.
When you are stressed, stop and think: do I really need to be in this situation? The answer may surprise you. Most of the time, you can either walk away from the stressful condition, or learn to steer the stress in such a way that it helps you knock off some rough spots that you actually have wanted to change but never had the motivation to accomplish.
Don't just try to tolerate the intolerable. because, if you do, you will never grow.