It isn't normal, but you show me two relationships that are the same and I will give you the Willy Wonka ticket :)
It reminds me on another bent when my wife and I were not married. Folks would find out we weren't but together, and the stink eye would happen.
One couple it was their third marriage, after cheating on their 2nd spouses and divorcing.
We added up the sum of both of their marriages and it was less then the committed between my wife and I.
My comment was ... isn't it sexy when stupidity and hypocrisy marry?
That being said I understand the hellscape of committed relationships with damaged people and being damaged myself.
So I never judge "ever" ... but I am all-in .... that if it is normal we lived in fucked up times with little hope, so I will side with a better tomorrow and say it isn't normal ....