RE: can i learn to fly without an instructor
I taught myself to fly control line. It took me a summer and many crashes and I now fly with my handle upside down in relation to everyone else. My point is that I spent a lot of time and effort learning mistakes. If I had had the assistance of an experienced instructor I would be much better off today.
I have flown alone a good bit. It is indeed more dangerous than flying with others. You have to be completely responsible for situational awareness. This means you cannot concentrate on flying as much as you would like, plus your situational awareness is probably not what it should be. As said, if you have a problem, there is no help. Twice I have had to drive myself to the emergency room.
Jim