[arethuza]

I would discuss this with your co-founders - highly likely that they are in the same situation. Agree a schedule where you can all get breaks while remaining in touch to handle emergencies - I'd suggest a couple of phone calls a day (first thing in morning and in evening) rather than email/slack/whatever.

Personally, I found that when I was in a similar situation years ago going on a vacation where you do something helps a lot. My wife arranged a vacation and signed me up for a few dinghy sailing courses - which I hadn't done before and they were brilliant.