The simple present tense is used:
1 To express habits, general truths, repeated actions or unchanging situations, emotions [states of being, in particular like being sick] and wishes [all those are particular cases of what is called the state present]:
I smoke (habit); I work in London (unchanging situation); London is a large city (general truth), [I feel sick all the time.]
2 To give instructions or directions:
You walk for two hundred meters, then you turn left.
3 To express fixed arrangements, present or future:
Your exam starts at 09.00
4 To express future time, after some conjunctions: after, when, before, as soon as, until:
He'll give it to you when you come next Saturday.
Be careful! The simple present is not used to express actions happening now [except in commentaries about sporting event, mainly].
He drinks tea at breakfast.
She only eats fish.
They watch television regularly.
For repeated actions or events
We catch the bus every morning.
It rains every afternoon in the hot season.
They drive to Monaco every summer.
- For general truths
Water freezes at zero degrees.
The Earth revolves around the Sun.
Her mother is Peruvian.
- [repeated action]
[The counter gets up to 10 then gos back to zero and back to 10 until you stop it.]
[In can't stand the noise of waterfalls. Fog depresses me.
2/ For instructions or directions
Open the packet and pour the contents into hot water.
You take the No.6 bus to Watney and then the No.10 to Bedford.
3/ For fixed arrangements
His mother arrives tomorrow.
Our holiday starts on the 26th March
4/ With future constructions
She'll see you before she leaves.
We'll give it to her when she arrives.
[5/] The historical present is the use of a verb phrase in the present tense to refer to an event that took place in the past. In narratives, the historical present may be used to create an effect of immediacy. Also called the "historic present, dramatic present, and narrative present."
In " she feels depressed" this is obviously not the historical present; of all the other possibilities the only one that makes sense is the state present (feeling sick as an unchanging situation).
In the case of "hungry" it is different; hunger is normally a sensation that does not last. suppose however that the word were used figuratively in a sentence as " I am hungry for novels that tell the truth." It's clear that the feeling is permanent; in this case, in order to communicate this permanent aspect you will do much better using the state present. The rare case of a person who is hungry all the time is not so farfetched but rather rare and in that case, because people are not familiar with this situation, you would add a little precision that makes unmistakeable that the tense is the state present; doing so you could say "He told me that he is hungry all the time.