depends on who everyone is playing, the positioning, vision, game time, objectives still up and a lot of other factors, but the first step is to quit whining about it. That 17/0 Darius will still have to wait for the respawn after his health hits 0, and will be giving some serious shutdown gold, which goes to your entire team, and you can use the time they spend dead to take objectives and get map control, make sure to shop before you run into that enemy again and that lead they had from being fed is now way smaller than it was, making it easier to kill them next time.
Another thing you can do is to draw pressure from the other parts of the map, I main mid right now and it's completely normal for the enemy team to have 3 people in my lane before the 5 minute mark, aside from jungle ganks I've got supports and top laners roaming on me to try to help their mid laner, I prefer the jungle ganks though because the buffs are pretty nice for laning, red or blue, doesn't matter.
As worried as you are about your team mates how worried are you about yourself? How is your CS at 10 minutes compared to the average? Does it fall off later into the game? Could a better opponent punish your positioning even though the current one can't? Is every one on the enemy team visible on the mini map when you're pushed up? What item are you getting next when you back and how much gold does it cost? How long until your wards expire? When are your enemies power spikes? if you are worried about your team mates you aren't focusing on any of this.