Tell someone about it
That's pretty simple advice that in practice can be very hard to do. But like any other condition, we have to admit that we have it before we can start to do something about it. And once we've made that admission we're going to need some help, even if it's just moral support, to move on.
In general, Shy Bladder sufferers don't talk about it. After all, peeing is the most natural thing in the world and being unable to pee is just, well, weird, so we don't want to admit it to friends or family.
So we stay locked in the secret prisons of our own making.
It took a few years of marriage before I was ready to explain my Shy Bladder to my wife. By then she already knew something was up. She thought I had a bladder of steel since I never seemed to need to go but at the same time she knew that I always closed the door firmly in the bathroom and couldn't take a pee behind a tree in the woods unless I knew she was way off up the path.
Telling her took a great weight off me. I had shared my big secret! I wasn't alone anymore. Suddenly odd behaviour that had previously puzzled her became clear : "Oh! That's why you always seem to go off to the farthest bathroom!".
Some people are not so lucky. When you have Shy Bladder your choices become limited in ways that people who don't have the condition can't understand. You may avoid large public gatherings because you can't use the crowded bathrooms. That means never going to the theater, the movies, sports events. If you have a really bad case of Shy Bladder you may only be able to use one "safe" bathroom (usually at home), in time that can make you virtually house-bound.
How many lives and marriages has that destroyed? When you can't do something but can't admit to the real reasons behind it people make up reasons of their own. He won't take me out because he doesn't love me / he's mean. He hates my family. He doesn't have any drive in business because he won't take the job that requires travel.
So if you suffer Shy Bladder, my best advice is to tell the other people in your life that your Shy Bladder is also affecting. You're not alone, there are millions of people like you and me.
I don't think I could have started to reclaim my life without this first difficult step.