Non-PRO Japanese to English Art/Literary Cinema, Film, TV, Drama

Dear ProZ members,

could you please clarify me the grammatical structure of the following sentence?

In a cartoon, a girl suddenly finds herself at the entrance of a Shinto shrine, with toriis and all, and she starts thinking she might be dead.

私の命は いつの間にか今生から果ててしまっていたのだろうか

I guess the meaning should be something like "Could it be that my life in this world has come to an end without me realizing it?".
However, what about that 今生から果ててしまっていた? Why から?

I get it as "coming to an end from this world", and it sounds odd to me. Is this usual in Japanese? Or I'm getting something wrong in the sentence?

Thank you!