1. You quit working on a client project. It's not clear whether you notified anybody, but it sounds like the work was billable until you decided to abandon it - which means your participation had to be replaced or written off, both of which are a bit expensive.
2. You don't know when you'll reach point X with the SEM project, and all you have been promised when you do reach it is an audition to ask for capital investment.
3. You have almost run out of cash because you spent it on stuff like an iPhone 4 when it was flowing, and are probably eating nothing but junk food.
It sounds like you're immersing yourself in dealing with the problems of coding in order to avoid dealing with the less tractable problems of money, personal interaction, and working pattern. You say nothing about attempting to sell your product elsewhere: it seems you don't like selling, and/or the product may be in a legal grey area in that the company in Charleston may have a claim on the IP because they paid you to work on it.
This is an unhealthy situation in multiple ways. I suggest you borrow some money from where you can to pay off your landlord and live for the next month or two on a basic but healthy diet. Then, look for a job. If your relationship with your friend is still good, then ask him to evaluate your progress so far, set short-term milestones for incremental improvements, and limit the amount of time you put into it until your financial emergency is over. If you are isolated, indebted and anxious then your non-provable design theories (UI, architecture) are probably not very good. This says nothing about your skill, it's because you refer to 'a horrible string of rewrites, starts from scratch, and UI redesigns.' That's what happens when you lose perspective and confidence at the same time.
At present you are your own employer, and you are mistreating yourself as an employee by failing to provide yourself with a paycheck or other forms of professional support. Quit your abusive job and see to your basic needs first.