I think the "Dump Echo" is a great way to look at it.
One of my long-distance plates just ended things today. She still really likes me but life stages, other excuses, blah blah. She was already talking about checking back in down the line.
I told her that if she thinks she'll be checking back in down the line then I'm expecting her to get her a$$ to my city and make the effort or I'm not interested at all. She agreed and we got off the phone. She sounded like she wanted to cry, and was calling me "honey" even as we said goodbye. I don't think they expect you to so easily agree with the breakup, which is the first step in setting them off-balance.
I have no doubt that this one will be back, as she's still liking my posts on facebook, I just got hired at a new firm by my mentor and I'm practicing exactly the law I went to school for, and everything is lining up. Plus, my birthday is two months away and there's lots more updates on social media that will be great for me, so she'll be thinking of me like crazy.
The key is maintaining my frame. If she's walking away now, she's going to have to work even harder when she wants back in. It's okay to respond if she reaches out, but you just assume that she wants to see you and try to make plans. In my case, I'll respond with something like, "Great to hear from you. So when were you thinking of coming to [my city]?" then if she doesn't talk about meeting up, or gets flaky or makes excuses, you say you've got to go, and tell her to keep in touch. In other words, if she's the one who ended things, she's got to make the effort to see you again or she loses you forever. If she's unwilling to, it's sad, but you'll move on.
Plus, when she wants back in, any good attorney knows that proper negotiation means you don't accept the same terms when one party cancels a contract. There's got to be something even better on the table, better terms, before the canceled-on party will accept the new terms. Even after you get what you want on your terms, you have to be willing to walk away.