I would not say I "learned" ancient Greek, because I have not, although I do enjoy learning it. When I ran across Xenophon's Anabasis in Greek, then found an English version to go along with it, I was pretty much hooked after that. Additionally, I had been reading things about Greek Tragedies, and the Pre-Socratic philosophers . . . they are very interesting. Also came across John Williams White's "First Greek Book", for learning Greek . . . and I concur, it was pretty tough going. Sometime after that, I wrote a program that is centered around making the study of Greek in a book like that much easier, and, it is also geared toward learning other European languages too. That program is currently on my GitHub site, (https://github.com/Skywola/Study-Maestro) but I have yet to complete the tutorial for it.
There is an element in Greek Tragedy that approaches the notion of defying the gods, you will find it in Greek Tragedy, and in stories like that of Prometheus, Sisyphus . . . . there was an inner mental strength that they had, at least the Greek writers who approached this subject. It came before the pollution and poison we call Christianity. So aside from the ancient history that I love, there is also an ideological element.
As for my learning of languages, I generally do not look at it like most people, and I generally do not follow the type of study programs they do. While I do study grammar, (and I have been using the quiz-maker in the program I wrote to improve my grammar), most of what I learn, I learn either from just reading, hearing and watching movies.
If you remember when you were a child, when you went to school, you would often hear your classmates parroting what they had heard on the radio or TV. Most people are under the false notion that children learn languages faster than adults do, I do not buy into that . . . . it takes a child roughly about 18 - 22 years to master their own language to a very competent degree. To say that adults are slower is just plain hogwash, unless you take the level of motivation into consideration. Children are highly motivated because they are constantly unable to understand everything adults are saying, so their curiosity is alive and well, and they have plenty of motivation, something that adults may lack.
If you like ancient history Xenophon's Anabasis might be a good read, but I recently ran across Plutarch's account of the affair and I am a bit more inclined to believe his version over Xenophon's.

As for the Pre-Socratic philosophers . . . . here is my favorite, and it is a damn shame that his writings did not survive . . . [en.wikipedia.org]

@THHA. You are certainly an interesting individual. I have read some of the Greek epic poems (in translation of course). I will check out your refetences. Thanks