Making up for a bad player in a team?

I've recently run into a pretty bad losing streak. Before, I'd play as a 5 man team and we'd win often, like 8 out of 10 games often winning. Over the past week or so we haven't all had matching schedules so most games are played right now as 2 man or 3 man groups, with 2 or 3 random people we're playing with.

I really don't like blaming teammates on a loss game, I think that's not fair in a team game, but a lot of games fall down from lack of proper plays or lack in communication in general. We all ping enemies missing, dangers, tell when we are starting a team fight or strategy, but with the lack of voice communication it feels like it doesn't always go through. The last game I played we had no jungler and an Annie top who fed and did nothing, and an mid Ezreal who refused to pick jungle when he saw Annie already locked in, who also never pinged missings or really do anything helpful, besides complain that their Nunu jungler had complete realm over the entire map because only us in the voice chat were buying wards.

I'm at a loss, and I feel like I'm coming off as a dick, but I'm really at a loss on how to make up for a lack of a team member. I assume the best bet would be playing as a hyper-carry, but even then I'm not too sure if that's even the issue, and not something wrong with me and the group I play with.