La vie a deux is very idiomatic. Sometimes it will mean 'living together', sometimes 'life as a couple', sometimes 'what it is like to live with someone'.
Look at what it is likely to mean in context, than select the most natural English expression from this general sense.
la bonne vie means 'the good life' in French.
"la vie est ainsi faite" (fixed expression, but a bit out-of-date nowadays).These days you would more likely hear "c'est ça la vie" or "c'est comme ça la vie"
"C'est la vie" = "That's life!". I'm guessing that "si la vie" is a mis-spelling of "c'est la vie!"? "C'est la vie" is a contraction of "Ce est la vie" ("ce est" contracts to "c'est"). "c'est" is pronounced similarly to "say" in English. Spanish "si" is pronounced similarly to "see" in English. ce = this/that est = is la = the (feminine definite article) vie = life So literally, "that is the life". But the "la" always accompanies the noun in French, and isn't relevant in the English translation. So think of "la vie" as translating in one unit to "life", as opposed to "the life". So the phrase means: "That's life!", similar to "That's the way life goes ...".
la vie vous donne espoir means life gives you hope
c'est la vie
The duration of La Vie à deux is 1.67 hours.
life
La Vie à deux was created on 1958-09-24.
The good life
La vie est trop injuste means "life is too unfair" in English.
"C'est la vie" is a common English colloquialism taken from the French phrase to mean, "Such is life". Literal translation: "It's life"
The literal translation is "the military life."
The cast of La vie en deux - 1980 includes: Erika Blanc as herself
la belle vie
'life is a sleep'
"vous allumez mon amour de la vie" means "you are lighting my love of life" in English.
la bonne vie means 'the good life' in French.