I can relate to this. Indeed my anti-social behavior cost me a marriage some decades ago.
You can get through this, and come out the other side a completely different person. Indeed it was losing my wife to be that made me determined to combat the condition.
Those were pre-internet days and it was a long lonely path to tread. But you can walk that while getting out and about, hopefully ending up in a scenario whereby you pop in the gents without giving paruresis a second thought. You never completely beat it, but you can come pretty damn close.
I recommend you go to a workshop, not been myself but I hear they help.
Or feel free to drop me an e-mail if I can be of any help.
Good luck with your journey - you are not alone!