Then when all things are clear from the legal side, first try to get this to work (if you still have any hope for this guy). Sit down with him and honestly talk about what you have in mind, and tell him you want to make this work. And make him commit to several things by certain time.
Or you could just tell him you want to split up. (Again, after talking to a lawyer).
You wrote 100% of your code and there was no legally binding document that transfers your ownership so I think it should be fine, but really really I suggest you talk to a lawyer if you are serious about this business. It's worth the money.
This will not be inexpensive to set up (a couple thousand in legal fees), but if you're ready to launch and want to clean up your legal situation, it could be worthwhile.
Right now you would likely be considered to have a partnership, and you each have rights under that (which vary from state to state). If you go off and build this on your own without a document that your friend has signed, you'll be on shaky ground if he/she comes back after you've become successful. For what it's worth, I am a former lawyer (but never specialized in this particular area of law).
> Then again, I don't know if you yourself are that committed either. A month and a half off from work to prepare a speech means you're not fully committed.
No, that was simply a mistake. I'm not going to take on any such side commitments for the foreseeable future. I recognized the mistake and course-corrected.