I would first explain to them that a healthy mind is like a healthy body: it needs to be looked after, and many countries take mental health seriously, without any stigma attached.
The fact is that most people could benefit from or need counselling or psychiatry of some kind, although relatively few realize its benefits.
Western people have had a cultural history of understanding the mind. Everyone has heard of Jung or Freud; words like ego, complex, paranoid, etc are everyday phrases. Therapy does not really have the same stigma it used to. Rather its often viewed as a luxury to be indulged by the rich and famous.