I’m not afraid of water. I had a little past history trauma as you call it with roaches in the tub. it was one of them claw foot tubs. I was very young. Ever since then I have a fear of showers I would get in but I try to avoid the situtionPhobia of Shower
Phobia of Shower
You are right: What you are describing is a phobia. You also know what caused it. The fear is certainly real to you. But you also know that generalizing from one experience when you were young to a fear of all showers forever isn’t rational.
Fortunately, phobias are fairly easy to treat. You need to see a therapist who can take you through a systematic desensitization. Your therapist will help you learn self-calming techniques. Then the two of you will decide on small steps that you can take, one by one, to help you get over your fear. You might start with just standing next to the shower and calming yourself. Gradually, you’ll build up to being able to take a shower or bath without fear.
I wish you well.