I have been thinking seriously about planning a long term backpacking trip. Something like half of the USA. Now I may sound crazy (maybe not so some of you...yet) but I was wondering, first off how I would get started on such a long term trip? I do not have a whole lot of experience, but I have dedication and motivation so I think it would be perfect for me to really start to get into things.

I do have a pretty serious mental illness called bipolar type 1. I have to take medications, on a regular basis. This adds another level of difficulty, but I would really like to be able to concur this, and prove that I can do it. To get back to myself after the first real bad spout. I would like to believe this is possible, any input would be greatly appreciated. Even if you do not have the information on the mental illness.
Thanks