released at the time it arises lets you stay balanced and aligned with the law of allowing. Sadness says a cycle has ended. Sadness can be about how long it has taken you to realize that your joy and compassion is found within you. Sadness over a thing that has ended is very common and needs to be owned and released. You grieve and cry for what was known, lost or changed. Events changing are just part of the cosmic quantum energy flow!
They were never designed for you to move into their energy field and stagnate there. Stagnating in ANY energy field means the quantum spin slows, collects matter and gets heavier. Stagnating in your thoughts of sadness and your perceived loss, may turn into fear that you are being punished. Feeling punished can move into your anger about being abandoned. Prolonged sorrow turns into depression and hopelessness or anger leaving you frozen.