Formal:
* La vie continue. (This is the most literal translation and the most common way to say it.)
Informal:
* La vie est comme ça. (Life is like that.)
* La vie fait son chemin. (Life goes its own way.)
* On continue à vivre. (We keep living.)
* Il faut avancer. (We have to move forward.)
* Il faut vivre. (We have to live.)
Figurative:
* La roue tourne. (The wheel turns.)
* Le temps passe. (Time passes.)
You can also use phrases like:
* Il faut savoir se relever. (We have to know how to get back up.)
* Il faut tourner la page. (We have to turn the page.)
The best translation will depend on the specific situation and the message you want to convey.