I never really get why people say "my better half".
I suppose when you're English native speaker it sounds okay since you don't know any better as it's a normal expression to use.
But to me, a near-native speaker English, it sounds and certainly feels off.

It's like saying that you are not much good, kind of like knocking yourself.
To me it feels like placing your value and worth in something external, in this case a partner.

Is it referred to the same way in other languages?
In mine we say what would translate to "sharer half" or "sharer partaker".

It's likely because English isn't my native tongue, or is it?
Does any native speaker feel the same way about this?

Something definitively lost in translation
there.

It is meant as a nod to the other half of
the relationship..in a positive way,
meaning they are worthy of being called
'my better half'.