ALL pain comes from attachment. Attachment comes from a desire for things to remain the same. Pain are feelings of anger, despair or sadness.
But nothing can remain permanent. Outer circumstances and people are constantly changing. Change might be gradual and imperceptible, like the growth of a seedling to a tree. Or change might be drastic, turning your world upside down, as the global COVID19 quarantine of 2020.
In our subconscious mind, the past is still happening in the present. The dynamics, conflict and patterns of the past continue in the present. People are unaware that the things they see in the world are coloured by the past.
When there is a desire for things to remain the same, people become attached. When you realise that things have changed, pain arises. Some reject the pain by placing the blame on others and seeking revenge. Some accept the pain, learn its lessons and heal.
Be de-attached and learn its lessons. Be present and move forward into your future.