Dating on the internet is not a bad START, but it can't be the only thing. And if he hasn't replied in 3 weeks, focus on someone and something else. The fact is, you have no idea what happened to him because you don't actually know him. You only know his online persona. He could have been arrested. He could have been found out by his wife (good point, Bonfire). His computer could have broken. He could have joined the circus. He could have moved adopted an anti-technology viewpoint. He could have been abducted by Bigfoot (and the internet service in the forest is notoriously spotty). It could be anything really. But more importantly, why does it even matter? I can understand if you care for this guy, but if the relationship hasn't moved beyond internet dates yet, it can't be considered too serious yet.
Good luck.
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