I suppose there is a balance between a modesty of the body and a certain unhealthy prudery.The Catechism can only give us guidelines as to where natural nudity amongst the same sex and where this behaviour crosses the line offending modesty.
As the previous lady has rightly pointed out,cultural practises play a big part in this,for instance 2524 of the Catholic Catechism states—“The forms of modesty vary from one culture to another.Everywhere,however,modesty exists as an instuition of the spiritual dignity proper to man.It is born with the wakening consciousness of being a subject.Teaching modesty to children and adolescents means awakening in them respect for the human person.”
We are required to be pure in body,mind and heart;in 2516 the Church teaches in a quotation from the great teacher of The Theology of The Body-----"For the Apostle it is not a matter of despising and condemning the body which with the spiritual soul constitutes man’s nature and personal subjectivity.Rather,he is concerned with the morally good or bad works,or better,the permanent dispositions–virtues and vises-which are the fruit of submission(in the first case) or the resistance(in the second case) to the saving action of The Holy Spirit.For this reason the Apostle writes.“If we live by The Spirit,let us also walk by the Spirit”
I believe Pope John Paul encounted in his pastoral duties this attitute to the nude human body that you describe ;where this person seemed to have an apparent unhealthy view .The errors of Jansenism still remains even in our “modern” society;where the human body is seen to be evil in itself.One religious Marist(the French Orders were very affected) Brother told me that he remembers, as a novice that they were to shower privately BUT they had on a “bathing robe” so they would not look at their nude body ,as they washed under neath the robe!!
When I was at the army cadet camps when at school,all the boys showered as a group in the open shower set up of the military ,with a school master watching on and turning off the main supply after 120seconds!! I did not think it was a big deal,neither did my fellow students.I think that you have a health attitude to your body in my view ;so do not change!