APC vs tank heavy teams.

I speak about Katarina specifically but I think this can apply to other certain apc's as well.

I've been playing a lot of Katarina lately and find that when the enemy team has 3 or even 2 heavy tanks I find it almost impossible to get through the frontline. If I manage to somehow reach the squishies, the backline usually has the awareness to have seen me trying to get passed their frontline for the past few moments. Coming from the side has ended up being a bad idea more often than a good one because they can feign ignorance to my position and/or take advantage of a split team.

I cannot poke down the frontline because all I have is my q, and in my experience it's suicidal to try and flash + e + combo + zhonyas + e out.

this has happened in about 4 games. I'm the only person fed on my team and the only way I think I can can carry is to eliminate the squishies because tanks take to long to kill and i'm cc'd to death before I can get a reset off one. I know Katarina can solo carry games but i'm stuck with these tanks.

I always get void staff 3rd item if I think the tanks will be troublesome. I have tried Liandry's + Rylai's but I feel that having a dot on Kat isn't how she should be played.

Just had a game vs and trying to kill anyone would always end up in me dying. Should I just suicide and try to cause as much of an issue for the enemy team as possible or sit back and hope my team can get them low? This last game I kept waiting for my team to do decent in a team fight so I could come in after cc had been used but they just let them push up to our inhibit and the game was out of hand by then.