It's getting stupid...how do I carry them >.>

You don't. Your best bet is holding onto 2 points until they come back while praying they actually come back. You'll otherwise need a perfect storm situation of them being bad, your team being pro, some help with the champ matchup, and some luck to actually win. Half the time it's a better use of your time to let them 5 cap because they'll never come back.

I found an awesome solution: Kayle

If they ever reconnect, it is easy to come back and win the game, since they are still gaining exp/gold while afking.

Best bet is to hold on to two points and try to get kills bottom lane.