From the second noble truth, we know that suffering (dukkha) is caused by craving (tanha). From the third noble truth, we know that the cessation of suffering comes through the cessation of craving.
What is craving really?
From this answer, we learn that craving is a habit of reification or objectification-classification (papañca). I quote that answer here:
Reification is simpistic naive superficial perception. It's a
generalization of the same problem that children have with toys. A
child sees a new shiny toy and because he does not think deeply,
because his perception is superficial - in his mind the toy is
attractive and desirable.
Reification is seeing the outer image and buying into its glow, its
fake promise to make you happy.
Meanwhile, in this question, I quoted Sutta Nipata 4.14:
Seeing in what way is a monk unbound, clinging to nothing in the
world?"
"He should put an entire stop to the root of
objectification-classifications (papañca): 'I am the thinker.'
Commentary (Thanissaro):
The perception, "I am the thinker" lies at the root of these classifications in that it reads into the
immediate present a set of distinctions — I/not-I; being/not-being;
thinker/thought; identity/non-identity — that then can proliferate
into mental and physical conflict. The conceit inherent in this
perception thus forms a fetter on the mind. To become unbound, one
must learn to examine these distinctions — which we all take for
granted — to see that they are simply assumptions that are not
inherent in experience, and that we would be better off to be able to
drop them.
Now what is the notion of the self? It's a mental fabrication. It's a view. It's a thought in the mind.
Due to this deep-seated thought or view of "I am the thinker" i.e. the notion of the self, one reifies everything that is perceived through the six senses into objects and classifies them according to its relationship to the self. It creates the duality of self and non-self, as well as classifies the relationship of non-self things to the self e.g. this belongs to me, that does not belong to me. Without the notion of the self, this reification would not exist.
And craving is, as said above, just a habit of reification.
For e.g. when you look at food that looks interesting to you, you experience craving. When the food is not present and you think about it, that's clinging. When you try to get this food, but it is denied to you, you experience anger. If somebody else took the last piece of that food and it is denied to you, you feel jealous as you see them relishing it.
To you, that meat thing on the plate looks like delicious food. To a vegan, that may look repulsive.
Why is this the case? That thing on the plate is just a thing. It's your mind that objectified it and classified it as delicious food. The vegan's mind objectified it and classified it as repulsive food.
Isn't it delicious food, only relative to you (the self) and your eating preferences (some characteristic of your personality i.e. part of your self)?
To a honey bee, that meat thing on the plate is not even food, because that's not the kind of food that it eats. That's just dirt to the bee. The bee objectifies it and classifies it relative to its self.
So, all types of craving and clinging and views are all relative to your self. If there is no notion of self, then the (sight and smell of the) thing on the plate is just something on the plate, that evokes no emotion.
So, all forms of sufferings are indeed related to the notion of the self.