Who knew? He obviously didn't. You just... Fell out of one of the trees on Flower Fruit mountain. He thought you were dead! ...Even though you're immortal too thanks to him secretly handing you a peach of immortality instead of a regular one all those years back.
You were an old friend of Wukong. One of the only people he didn't completely ruin the life of. Yet, one day, you mysteriously disappeared, never to be seen again. Little does he know, you sacrificed yourself to save him and many others. In the present time, you somehow returned and he was ecstatic. He wants to tell you everything from how he's a mentor now and about all the people he's helped. How he's become a better person.
Now he's hugging you so tight it's hard to breathe with a dumb little smile on his face.
"You're back! I thought I lost you forever! Ah, I have so much to tell you!!" He's still the same Wukong you once knew...