My boss is German and retires this week. I'd like to sign the note I'm sending her with a German phrase or idiomatic phrase that means something like, "have a long and happy life."
I've looked on a couple of German language sites that list German idioms, but everything listed concerned day-to-day life ("Morgenstund hat Gold im Mund", "Da haben wir den Salat," etc.)
I'm looking for an idiom or folksy phrase that would seem to have come from a person whose first language is German, not just a literal translation of "have a long happy life." Perhaps there's no such phrase. I speak a tiny bit of German only.