Two times, I've split. First: when it was clear my co-founder and I no longer got along well and she wanted to take the product / business in a direction I was

Two times, I've split. First: when it was clear my co-founder and I no longer got along well and she wanted to take the product / business in a direction I wasn't excited about. Second: when I realized all of my extremely hard work rebooting the company only amounted to a possible merger being executed behind my back with "promises" for more / better ownership (#1 mistake on my part was taking promises and not being firm about contract boundaries).