Why not hire someone to run the company for you or at least handle the majority of day-to-day operations? Possibly promoting one of your existing employees into a leadership role or "co-founder" role if this is something you would consider.

I would be upfront with your employees now. Maybe one of them has an option you have overlooked completely. Also, if you are honest with them now, it may help with any potential outcome down the road (for example, if you do end up having to shut down it is not a complete surprise to them). Also, by opening up about it, you might consider posting more details about the company here. Who knows maybe there is someone here who would consider making the purchase or taking it over for you.

Just a couple thoughts. Good luck!