Facing chronic fears gradually works through Detachment from elements triggering Phobias.

Phobias are irrational fears of traumatic origin.
90% of phobias develop in childhood and are easily overlooked as a natural developmental learning factor.

The fear of water is the most primordial manifestation in newborns, nobody is exempt however, if it persists through adulthood, it should be addressed.
Plenty of adults dread water, they are terrified of drowning and swimming.
A significant percentage feels suffocating under rushing showers.
The Medical term for this fear is ‘Ablutophobia’, although hardly addressed for shame of poor hygiene, despite sufferers being equally if not cleaner than today s average triple-daily-shower neurotypicals.

Phobias are hard to treat in adulthood, although latest research suggests there is hope with strong Commitment, Mindfulness and ultimately Desensitization. 

The biology of Phobias is well documented.
Each phobia is normally associated to six symptoms, so called ‘Phobic Ladder’.
Symptoms must be tackled individually, starting with the most disabling.

The latest entertained view of phobias in adults is Boredom.
Any action, pleasurable or not, becomes bothersome when compulsory.
I can confirm it. I dread showering even when I’m off. 
I’m working through Desensitization and make showering a pleasant habit.

This applies to any phobia.
As usual, easy said than done.
Nothing happens overnight.

The pharmacological implementation is symptomatic, with benzodiazepines and SSRIs as first choice.