How can it be?
Lets see, what is the meaning of “intended” in the first place?
You certainly will find that one of the meanings was “someone that was intended to be someone’s wife or husband”. Therefore, the “un” affix before “intended” will born a new “ex intended” meaning as I told earlier.
most of you may ask, “Is there any example for it?”
Well, there is.
One most popular example is a song by Muse entitled “Unintended”.
I’m personally prefer to interpret “unintended” in that song as a “wife”.
Check it out! :D
In the first verse of the song is written:
You could be my unintended,
Choice to live my life extended
You could be the one I'll always love
If you willingly listen to the continuation of the song lyrics, then you’ll see my reason in using “wife” to understand “unintended”. :)
English is fun! Even though it is not my mother tongue…. :)