Nouns ending in -ie are usually feminine.
The suffix often names an abstract quality, an activity, or a discipline.
Is vie masculine or feminine?
lavie
The rule behind it
95.7% of -ie nouns are feminine
In context
Le coût de la vie a augmenté radicalement.
The cost of life increased drastically.
Pourquoi la vie est-elle si remplie de souffrance ?
Why is life so full of suffering?
Tu es le grand amour de ma vie.
You are the great love of my life.