一生 いっしょうモノじゃなかったです
isshō monojanakattadesu

Noun
Desu Copula
no-Adjective

The polite, past negative form of 一生モノ

1. It wasn't a lifelong thing.; It wasn't for life.; It wasn't a keeper.

Past/Perfective
Negative
Polite
Casual Register