Nine years ago, after we dropped our kid off on the morning school bus and were walking the mile or so we lived from the beach, my then-girlfriend told me she wanted to become my now-ex-girlfriend. It wouldn’t be fair to say it came completely out of left field, but it definitely had warning-track power. I never saw it coming. The stresses you don’t see do the most damage.
On the other hand, my ex and I were never going to make it as a couple. We weren’t built to last; we were open with each other that we didn’t want to be forever.