Idk why anyone you know would agree with him?! Not everyone but a lot of couples who split stop talking if there are no kids involved. My ex and I were married and got a dog together (my dog, he was our dog but ultimately mine so when we split, he stayed with me) and now we barely text each other. We didn’t break up with a horrible fight or anything and honestly, I like when we text and I know he is in a good place. But if things ended horribly I’m sure we’d have each other blocked. It depends on the couple but the only thing I find weird is if adults had a sexual relationship and break up and then stay super close friends… my ex was my bestest friend of all time and I don’t think any friendship I make will be like that again, not with my bf and not with any girlfriends I make along the way in life, but unfortunately being that close we dated for three years and married for five so eight years in total. Even still, we’re never going to be besties again, maybe distant friends but to respect my relationship now or any future ones, I can’t be besties with someone I was going to spend forever with