Recently, our daughter (17 in June) told my wife and me that she has started dating not 1, but 2 guys. No introductions needed since we already know them; they’ve been close friends of hers for quite some time now. Daughter put it as: why do I have to choose if I like them both and they don’t mind sharing?
I just don’t like it.
It’s perfectly fine to not like it and as long as you don’t force your view on your daughter, you are not a bad person.
But you sure as hell are a bad person if you don’t accept your daughters stance. Because as long as it is known to and accepted by all participants, it’s nobodies business but theirs. Nobody gets hurt by it? Nobody should interfere.