We're history.

[YOSHITAKEHORI]

I came across one story about high school students, John and Jane, which
were probably written by Japanese.
John and Jane loved each other but they were going to separate at the time
of graduation.
When they last saw each other, Jane said '' We're history''.
I thought she meant that they would not be able to go back to
past.

But I don't know whether this word '' We're history'' is correct on this occation or not. I feel odd about this word...Is it correct? and is it a frequent word ?

[gio]

I came across one story about high school students, John and Jane, which
were probably written by Japanese.
John and Jane loved each other but they were going to separate at the time
of graduation.
When they last saw each other, Jane said '' We're history''.
I thought she meant that they would not be able to go back to
past.
But I don't know whether this word '' We're history'' is correct on this occation or not. I feel odd about this word...Is it correct? and is it a frequent word ?

this phrase means that something has came to an end, is finished. doesn' t exist anymore.

[Coffa]

It's a very common colloquial idiom.

[YOSHITAKEHORI]

gio and coffa,
Thank you for your reply.

[Naughty Beef]

It seems a bit strong to me.

I always say it like 'good riddance'.