Maybe take a page out of the same book and find somebody for yourself (though maybe closer to home).

Rebound - Rebound - rebound it's called.

Work, that is. Your ex jumped into something new on the rebound. The chances for that relationship being successful in the long term aren’t very good. Especially the online plus distance thing. However, that’s no longer your problem. What is your problem is figuring out how to move on with your own life and put them firmly in the past. I know it hurts a lot, but really you have no other option unless you want to continue to suffer. Hugs for you.

As far as I know, they've only spent 7 - 10 days total together on a few weekends. I'm mostly just concerned they are making a big mistake and am not sure how their teenager fits into this. Guess I'll never know because they blocked me.

Your ex has multiple personalities?

Maybe the Op doesn’t want to reveal their ex’s gender or maybe “they” are the ex and the teenager.

The word “they” is not necessarily only used when referring to more than one person. “They” can also be used in relation to one person, such as in the case of the next sentence. Most likely the OP did not want to use gender specific pronouns, therefore, THEY used the word “they” instead.

have narrowly escaped a relationship from hell. Count your lucky stars.

So how long til you consider a person is past this" rebound mark"
You sound so "knowledgeable ".
I think each relationship is quite different, depends on the person.
Tell us magic guru.
Enlighten us.

Interesting not so fun fact: While women experience more pain after a breakup, we recover more fully than men ever do, reports new research from Binghamton University in New York and University College London.