romanticintermediateuniversal
Du bist die Liebe meines Lebens.
/duː bɪst diː ˈliːbə ˈmaɪnəs ˈleːbəns/
You're the love of my life.
When to use it
The big one. Reserved for the real one — wedding speeches, anniversaries.
In conversation
—Nach all den Jahren weiß ich es: Du bist die Liebe meines Lebens.
“—After all these years I know: you're the love of my life.”