Lee sin in the late game

So i've found that i can do fine with lee early game, but once it gets later on in the game (and this is a problem i have in general when im jungling) i find that i don't know what to do. Should i be pushing objectives? making calls? what's my job in teamfights? Just looking for some advice on how i should approach this stage in the game. The thing that led me to posting this was the result of a game i played yesterday. I was 12/0/1 at one point in the game, and our team as a whole was fed. However we hit a stage where we stopped taking towers/other objectives, and threw, giving the enemy team a comeback. They outscaled us late game (azir, ezreal, gangplank, oh god) and giving them a chance to comeback was our downfall. After our first throw we just couldn't get reorganized and got rekt.