Is it true that once a foreighner lives in japan too long, they become a little bit cold & distant?

Question:

Is that part of the assimilation process of becoming Japanese?

My Aunt told me that she had a friend Who was very happy-go-lucky & talkative & loud & expressive.

But she told me that after 3 years when her friend came back from Japan, that her personality changed and that now she is Cold & distant & reserved just like the Japanese.
& it changed her forever.
I think thats sad.
Is that what japanese society really is like? Cold & distant????
that is why she became that way?

Answer:

I didn't find the Japanese cold and distant.In fact I found them to be warm and welcoming, Couldn't help me enough. I made many friends and got on well with the majority of Japanese I met. Of course there was exceptions, especially the older generation who still had memories of another time.
Japan is different from other countries I've lived in so I had to adapt accordingly. For some people it's relatively easy, for others it's a bit of a nightmare apparently so I can understand why they may think the Japanese are a bit cold, distant and reserved.

I'm sorry your Aunts friends Is the way she is, and I wish her well.