Sorry to say it, but those numbers aren't really "carry" worthy, so there's not a whole lot you can do other than hope you get adequate team mates in your next match. If both teams have similar numbers to yours, it's a skill matchup between the teams. If everyone is feeding like in your games, if you can't stay below 2 or 3 deaths you are giving the enemy team too much time while you're dead to push their advantage against your other team mates. That accelerates their feeding and is practically a guaranteed loss. First rule, stay alive. Second rule, don't try and save team mates that repeatedly show they are not worth saving (for example, they just stand there at 100 hp taking skillshots to the face when they could have escaped) third rule, keep your cool and play smart.
Always play safe and smart wether you're ahead or behind and communicate what people should NOT be doing. Don't flame, inform them. I almost came back from a loss, and it would have been one for the books. We got maybe 2 of their outer turrets down. That was it. They had all three of our inhibitors down. We managed to defend through two barons made it all the way up to their nexus, but because everyone tunnel visioned on the nexus, they didn't notice vayne re spawned and wiped is out one-by-one (75second death timers) and they just rushed our base and finished it. Didn't matter that I pinged her multiple times and tried to stun her, they were too tunnelled because we were coming back! :P honestly I think I had the biggest impact on that almost comeback. Not because I dealt damage (I was Braum), but because I communicated. I had to tell multiple team mates not to push out the waves so far. We had no way to ward the jungle, and they were pushing out blind and getting collapsed on. I had to remind 2 different people at least three times that it was a horrible decision. I didn't flame them, I reminded them it was a bad choice and why. Only push when we have wards out, and we can only ward after winning team fights in our base, which we managed to do consistently. We got the priority targets , warded on our way out, took a turret or two (death timers permitting), rinse and repeat. We should have backed off when we got the second nexus turret because vayne was about to respawn. I pinged, I said in chat, but the tunnel vision lost us the game. If we backed off, we would have won another team fight and stormed in for the win.