Thank you for clarifying, Xyzcf.
I am not certain if the LBS being in a new relationship or marriage, or no longer wanting the MLCer back, stops the MLCer from trying to be back.
Real life MLCers I know, and there HS cases as well, thing Sewing22 who had her own crisis, try to get back even if the LBS is in a new relationship or marriage. It will be the LBS that will not take the MCLer back, not the MLCer who will not try to return.
Even MLCers who were physically abusive, like LP's husband, once out of the fog try to get back with the LBS. LP wants nothing to do with him. Or last time she posted about the matter, she didn't.
So, yes, the final choice is up to the LBS. The MLCer may want back, but if the LBS does not take them back, there will be no reconnection.
I don't think someone is wasting their life because they don't have someone in their life. It is up to each of us to decide what we want. I also don't mind if a LBS decides to have a new relationship or marriage.
I agree that jumping into a new relationship or marriage after BD, or until we aren't in a good place, is not a good idea. Even in a normal divorce it is not a good idea to quickly jump into a new relationship.
Sometimes good things fall apart so better things can fall together. (Marilyn Monroe)