[tptacek]

How you navigate this is you quit. You don't have a startup; you have an unstable pair of cofounders flailing to pick a startup to build. Every dollar you draw from your initial investment before securing product/market fit devalues your work. You and your partner have lost respect for each other and will likely sabotage any success you do find.

It's not clear to me what you're preserving by staying.

[JamesBarney]

100% this. If you guys had significant traction with your startup then it might be worth it to work really hard to try to salvage the relationship.

But right now you're just wasting your life. The most valuable resource you burn through at a startup is your life. Startups are stressful, they wear you down, they're not great for your finances, and many of those are doubly so if you don't get along with your cofounder.

Just quit, you don't owe anyone your life. You are less likely to find traction with two cofounders with a bad working relationship, and if you do find traction you are less likely to be able capitalize on it.

[tptacek]

I won't shut up about this, because I don't think most people can understand viscerally how much more valuable their time is than almost any other consideration until they've spent a lot of it already. People here obsess about equity stakes, but almost never about opportunity cost, which is what's really killing most of them.

Also? Working your ass off to save a shitty business relationship has a psychic cost. You do not have an unlimited reservoir of relationship energy to spend. If you want to keep doing startups, you need to guard your morale reserves. Wringing yourself out here won't just mess up your current startup (which seems fucked enough already); it can mess up your next one too.