Late game Lee Sin

Can somebody give me some tips on how to play Lee Sin late game. It seems like whenever I play him I snowball hard early game, and when late game comes it all just gets thrown away. For example, I was playing Lee and up until around 25 minutes i was 8/2/3. After that the entire enemy team decided to stop dying and start killing. I died in teamfights, towerdives, and eventually in my own base. I ended that game 8/7/4 with a loss. With that being said, can somebody give me some tips on how to make lee sin not fall off as hard.

Thanks in advance!!