Change your oil to something thinner. As stupid as this sounds, I had the exact same problem when I first got my car and I did everything you mentioned with no success. I was even able to get it started with your same method. It ended up being the oil was too thick and covering the spark thus not letting the car start. And when repeated attempts, the car ends up flooding. I switched to synthetic and haven't had the issue since.
Also check your plugs/wires and make sure there is no oil on them or anything.