Yes, it happens. .. thinking it's an indication of insecurity in who you are, and not really knowing yourself .. then taking on the expressions or mannerisms of someone you like and admire .. going with the flow is one thing, changing your behaviours and outlook on life is quite another.
When I was young, and newly out of the b'Org, I tried to 'fit in' with my crowd, but it never felt right. People picked up on the fact that I was a phoney, and I had few friends that lasted. Though I was always trying to be good and nice, I had no idea who I really was, and folks sensed that.
Now that I'm 'my own person'; sometimes cranky, and yes, opinionated, I have a lot more friends, and they stick around, because that is the real me.
It still happens occasionally, and I find myself gettin askeered when I catch myself doing it
Seriously, though, it seems normal that we would pick up little expressions, etc., when we are hanging out with someone, but changing your personality and ways of dealing with people is a sign of emotional immaturity and emptiness inside.
The other side of this, is that maybe that person has caused the other to do some thinking about life and how they feel ... maybe they have taken on a different viewpoint because the friendship has stimulated them towards inner reflection. Depends on the situation.
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