How do i play against Lulu?

I really have a problem with her, what i mean with that is that she just uses every spell on her teammate who carrys and her e on a fed enemie and he kills everything. Even if Lulu got stomped in lane and dont really has a good score she is still usefull. It really annoys me, and i really want to learn what to do against this. I btw. play jungle most of the times. Especially with Champions like Lee sin, Rengar or Olaf. [vlad-salute] Btw: sry if my english is bad, it isn´t my main languange and i never were good at this :)