Comfort with Discomfort

Becoming comfortable with your internal discomfort, is the first step to developing resilience and happiness. The most important element is the attitudinal change of acceptance with curiosity, care and openness. 

Physiological and Psychological Resilience + Executive Function

Responding to anxiety and distress can be regulated via two levels
1) Physiological resilience - the body becomes stronger towards stress after repeated exposure (but manageable) stress
2) Psychological resilience - the mind develops resilience towards stress after repeated exposure (but manageable) stress
3) Executive Intervention (such as mindfulness, meditation, "letting go", diversion of though) - regulation via the executive part of the brain (per-frontal cortex) through cognitive functions.

State of Being and Transitions

Being in a state does not guarantee staying in that state, control of state transition can be achieved through awareness and meta-cognitive practice.
For example you could be completely relaxed, but suddenly snap when your hot buttons are pressed. What can control you suddenly snapping is immediate awareness of what is happening and appropriate intervention before "amygdala hijack"