Thankyou for sharing your story Justinas. Fairplay to you. It affected me deeply. This condition is ####ing difficult and ####ing horrible, especially when it's severe and your story attests very eloquently to that.

It sounds similar in some ways to my own experience of shy bowel, though mine wasn't quite as severe (I could go in the family home but only if no visitors were in the house). Also had my first experience of parcopresis at 17. Felt and did pretty much exactly the same as you. It was back in the late eighties; I was just angry and frustrated at my body for not working. I drank lots of black coffee and smoked cigarettes to try and stimulate my body to go. Thought I could MAKE it happen consciously by sheer effort and desperate pushing. Just managed to make my intestines hurt more and feel bruised and in pain.

And then, as you put it so well, the fear sets in. And then you're into a vicious circle.

What's different about your story is that you don't have shy bladder (paruresis), you know that other people have parocpresis and you're not the only person with it. And you're starting to take it seriously and acknowledge it from a much younger age than I did. (I was in complete denial about both the shy bladder and the shy bowel and the Irritable Bowel Syndrome (IBS) (yep I got that too!) until my early thirties.
And those difference I feel sure will work in your favour.

There's a lot more I want to write in reply and I will in time. But I'll leave it there for today.

The anismus btw can be treated with biofeedback, so you can research that. You might even be able to do it at home if you can hold of the machine thing. But a therapist would be useful to help you challenge your thinking and bodily reactions even if you're checking in with them between sessions.

Hope you survived the Christmas season. It can be a nightmare time for people with this condition.

Will write more. Feel free to share more in the meantime.