In one Tibetan model, there are 3 types of suffering, or perhaps a better term would be unsatisfactoriness: Suffering, Change, and Pervasive Conditioning. The first two speak for themselves. The 3rd, Pervasive Conditioning, refers to that nagging background mind noise that almost constantly tells us that we would be happy if only we were somewhere else doing something different. It only goes away, it seems, when we sink into the samadhi of forgetting our self for a moment.


"No composite thing has permanence,
So cut your ties to them and be free of clinging.
There is no joy in the cycle of existence,
So engender the disenchantment of renunciation.
...
Habituation to delusion comes easily,
So send forth the spy of mindfulness.
Skilled you may be in gliding along on sensory objects;
Wake up, for they are of no use.
...
Whatever appears to your perceptions, leave them as they are;
This essential point ensures cyclic existence is liberated naturally.
...
This illness does not exist as an absolute reality, so pierce your grasping..."
Yangonpa


The mind goes in circles, from this to that to this to that to this to that to this to that to this...and on and on. This is the cycle of existence, repetitive history, habitual patterns, samsara. But it does not exist. Know that. And wake up.
Here is a teaching that happened in a dream. The first two lines were given by a man in a clothing store, who then morphed into a woman on the sidewalk outside the store:

Recognize your true nature.
Rest there.
Remove all doubts.
Roam freely, like a happy dog.