I might have a slightly different experience from some.
I did meet my TF on a dating app, but at the time, I was trying to actively casually date for once. I met three people in the same week, and my twin was the last one. I actually almost cancelled on her because she was “too perfect”.
I’d always dated people who were too similar to me, and she was more perfect than usual, so I kind of caught myself for a moment falling into a pattern.
I say this because I have definitely spoken to people online and felt some sort of familiarity, but I’ve also spoken to my twin and not been hit in the same way. She seemed sweet, and I was attracted to her, but it wasn’t until we physically met that it hit me, and that was immediate.
As for your main question on long distance, only for about 6 weeks. Not long after we met I had some prior commitments to take care of and normally I don’t answer my phone much or struggle with being phyiscally apart but with her… I was on my phone all the time. Also had that telepathy feeling. I still remember walking down the street to my local breakfast spot and feeling like she was beside me just chattering away.