Kübler-Ross noticed that the first stage in the journey was Shock and Denial. This stage is short-lived. Then come Anger, Bargaining and Depression in some order. These stages are not linear or sequential. In fact, people cycle through these three states (Anger, Bargaining and Depression) like a random walk along a Markov chain. The time period spent in such cycling could last hours or days or weeks or months. During these three stages, misery and suffering is experienced. The state of mind is exactly the state of mind corresponding to 'separation' in Sufi and Bhakti poetry.
Eventually, at some point of time, the last stage emerges. Using Markov chain terminology (which would be familiar to mathematicians and computer scientists), this is a 'terminal state' from which we don't jump to any other state. Do you know what it is called? Acceptance! The state of mind in this stage corresponds exactly to the state of mind in 'union' in Sufi and Bhakti poetry. It is only in this stage that peace is experienced.
Isn't it fascinating that the terminology in the 5-Stage Grief Recovery Model matches the concepts in Sufi & Bhakti poetry?