TLDR
Spoilers
Yada yadaaa

Ok so i recently plugged in the ole PS2 and started another play through of X. Now that i am older and actually care about the story linked between these two games, the more i want to understand the link between the two games as far as Tidus and Yuna are concerned. Mostly Tidus.

I never understood as a young boy why Tidus just vanished and then after playing X-2 was confused by the who shuyin/tidus look a like thing.

It really all starts with X-2 as it seems to provide better light into the war that created Sin. Bevelle vs Zanarkand. Lenne a singer/summoner of Zanarkand and Shuyin, her lover from Zanarkand who i also believe played blitzball.

During the war Zanarkand put summoners on the front line and Shuyin wanted to find a way to stop Lenne from having to do so. Shuyin's plan was to steal a powerful bevelle machina and use it to his advantage. Lenne shows up to prevent him from doing so and both end up being killed, Shuyin never hearing Lenne last words about how she loved him.

During the destruction of Zanarkand, Yu Yevon turned the survivors into the fayth which would create a dream Zanarkand. The place which Tidus and his father Jecht are from.

Yu Yevon then becomes sin and the cycle begins.

Now 1,000 years later we play X. Starts with Tidus bitching about his daddy issues and how he left 10 years ago blah blah. Boom dream Zanarkand is attacked by sin. We meet Auron, who is Tidus guardian, and after some events we find ourselves in Spira.

During the journey to defeat sin. We learn a few things.
1.) Sin is Tidus father Jecht. Sin invaded dream Zanarkand 10 years ago and took Jecht who was out out to sea training for blitzball.
2.) Jecht, like Tidus, became a guardian along side of Yuna's father and Auron. In destroyed " real " Zanarkand Yunas father Lord Braska, Auron, and Jecht met with Yu Yevons Daughter Yunalesca to obtain final Aeon.
3.) They find out a guardian must sacrifice themselves in order to become final Aeon and defeat sin. Yunalesca reveals the secret of sin and this pisses off Auron.
4.) Jecht becomes final Aeon, but before he does he makes Auron promise to take care of Tidus.
5.) Once that group beat sin. Auron goes on rampage and tries to kill Yunalesca only to be killed.
6.) Bound by his promise to Jecth and Yunas father to protect them he lingers Spira as some sort of ghost.

After the 6th sense type shite and Yunas crew destroys Sin for good. The fayth stop dreaming so Tidus goes away and Auron is no longer bound to his promise and goes away as well.

Now thats is the story in a large nut shell through my eyes, which makes me believe that Tidus if the reincarnation of shuyin. That one of the fayth living in " Real " Zanarkand that ends up dreaming creates tidus from the memory of Shuyin. I also think Yuna is a embodiment of lenne and that the past is kind of repeating itself.

Tidus and Yuna, the embodiment of Shuyin and Lenne finally get to be together, as previously stated Shuyin never got to hear lennes last words before they both died.

Thoughts?