serious question

what to do when your team cant teamfight?

i was fed as hell able to 1v3 but that doesnt mean anything when you take out 2 people and die as a fightliner and your team disengage at full hp only being slaughtered

i sold some damage items and got more tanky with 3600 hp 150 armor etc i would last 10-20secs in middle of a 5v5 before going down from cc's burst i kill something or 2 they all low my team untouched just started retreating.... vayne/yas chase them down they die we lose another teamfight....

i went in again i baited all the c's lived took 1 down started to slowly peel out my team follows suite retreating with me instead of killing people i get low... we lose another teamfight...

im stump at this point..... and next teamfight i get a nice 5 man knock up took them all real low beforei died and my full hp team is retreating dying 1 by 1 and they kill the nexas