Disclaimer: I don't own Tales of Symphonia, Namco Bandai do.
Immortality.
At first glance, certainly, it is indeed the greatest of blessings. Never aging, never dying, forever watching as the world changes and the days turn into years, decades, centuries.
But as time passes, this gift turns into the blackest of curses. All those you love and cherish wither and fade before your very eyes, whilst you stay the same. Being forever alone in your immortality, your only companion the memories that will slowly fade and shrivel like the spring time leaves in the dead of winter.
But if you should encounter another with this power, then it is as such the greatest gift you'll ever receive. Forever and ever with that person, never changing, never alone.
Lloyd.
When he laid eyes on his son that day, for the first time in so many years, his heart leapt with joy. His boy, his precious boy – he was alive! But alas, this ill-fated happiness was only to be short-lived...
Because as time passed, he realised something. Several things.
That while he was blessed with the grand gift of immortality...
Lloyd was not.
At first, he paid it no heed. He had his son back, and that was all that mattered.
They travelled on their journey. Broke the seals.
And then came that faithful day.
A tower. Blue eyes gone cold and unfeeling. Betrayal.
He did the one thing he'd hoped never to do – hurt him.
And the rest of their adventures followed after. Pacts were made, enemies fought, and the worlds reunited.
And in the end, he stood before his son. And asked of him the cruellest thing.
"Send me away."
And thus he left. Stood on the desolate rock as it drifted far, far away...
It wasn't till he'd lost sight of Aselia that he realised.
That while he was immortal, Lloyd was not.
And that he would spend eternity filled with regret.