These are really good answers and something I think about, too.
One thing I notice with people who "move on" and develop another relationship quickly is that they don't seem to be lasting ones.
Often what I see is these new, quick relationships built out of things like fear of being alone and sometimes other factors like stress bring people together quickly but it's in turmoil, not peaceful or lasting.
The term "rebound" comes to mind and even though being without romance and physical love is very hard and lonely, sometimes it seems better to try to heal further before involving someone else in our lives.
I think I would hope for the next person coming along in my life to be free of the baggage I have now, where even though X claims he is "over me", he brought a hell of a lot of baggage to OW that she accepts.
Another example is that X claimed harshly to have moved on but spends a lot of time looking back. I don't want that, either.
My mother I watched do the same thing and she got burnt very badly.
But I sure do understand the thoughts behind the question.
Yes, the posts that talk about what is considered "moving" on are good ones.
A person is a person, no matter how small. -Dr. Suess