Why do some people rebound so quickly after the end of a long term relationship?

Why do some people rebound so quickly after the end of a long term relationship?

I am not sure what to say on this, since all my relationships before getting married didn't last past a year.

My mother's cousin is in the separation process from her husband/partner (not sure if they were actually married or not) and both her and her ex jumped in new relationships as soon as they went official with their separation. Mind you that those guys have been together since they were in middle school and last year were proudly celebrating their 22nd anniversary together. It's like they just flipped a switch. Even their children have no idea what happened since they weren't arguing in front of them, although they are already grown and taking it well.

To me it's a bit serie honestly. Somehow it makes me think how in some ten years or twenty years my wife and I could wake up one morning and just call it quits. Meh.

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6 h
My opinion, which is shared by my wife and my mother, is that probably the passion fizzled out time ago but since they were getting along so well and not fighting, they decided to stick it out till the children were grown up while planning their separation. Hence the chill and serene way they split and why they jumped in new relationships so fast.
Why do some people rebound so quickly after the end of a long term relationship?
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