I do know how you feel. This all 'finding a toilet that nobody uses' sounds just too familiar. I am 22 and male. For me this whole thing started at high school. Much like you said, my body used to know when it was time for a number 2 until that crucial day. I was attending a lesson when I felt that something big was coming my way. I was too ashamed to use school toilet so I decided to excuse myself and flee home. I did not make it. I put a huge load of diarrhea on the halfway. It did not feel shocking at that moment. I remember thinking it could even be a topic for a stupid joke. But it was not until the following morning that I realized I had a phobia. I felt immense urge of defecating during the first lesson in the following morning. I could not go to school for half a year or so and I have had this phobia ever since. I started therapy a couple of years ago and I think that it is working it is only that the effect is so slow. Well, what I wanted to tell you is that there are a lot of people that understand the way you feel and that you should never ever give up!