Apply to an incubator. That's what they're for: providing connections.
Edit: Not opposed to taking on a cofounder if they provide an adequate amount of value other than pacifying incubator/accelerator/investor fears.
So, when you're a solo founder, it gives the vibe that you haven't figured that out yet (you won't even get another founder, even though it takes no cash, you have traction, etc.).
So, to counter that bias, just make it clear in your application that hiring people, finding a co-founder, etc. is VERY high on your priority list at the incubator.
Good luck!