when we think of how another might see us, we auto matically use the pronoun we think they will use.
This is more an acceptence of their perspective, then a change in our own.
Another situation, I reffer to myself differently is when, I talk about pre-out memories. This also has a habbit of changing the pronoun I use for another persons perspective too.
eg, Ill be sharing an old MEMORY the includes my sister, and ill say somthing like, and then she was like "I cnt belive he just did that"
But later, since she has gotten used to the new pronoun, ill say and she was like "I cant believe she just did that"