The interesting part is that you probably knew all of this going in. Perhaps you were so enamored with your idea, that you wanted to believe these were not the insurmountable challenges that they were. Reminds me of couples who marry knowing of certain glaring problems, but proceed anyway because they are "in love". Whether they downplay the problems, convince themselves they can overcome them or otherwise, these are frequently the very problems that lead them to failure (divorce).
But, more frequently, we probably just think these challenges will melt away or work themselves out somehow. Maybe that's why these businesses always look so good going in!
This is not to lambast you--quite the opposite actually. I have been there and I am still susceptible. I applaud you for acknowledging your challenges and getting out relatively early.
Good luck to you on your next venture!