It isn't the internet--there have always been people out there who specialize in "finding you" when you need a shoulder to cry on--they know that when you are hurt you are looking inward,
at yourself, and not outward, at them--because they can't deal with any kind of scrutiny--

At lot of times, the real reason that they "leave" is because you were close to finding out that they weren't really the wonderful person that had been pretending to be--

Don't blame yourself, because, in order to survive, these folks have learned how to put on a convincing act--

I've been through this, in fact, I remember a certain Valentine's Day, many years ago, when my wife at the time handed me a card with pictures of cockroaches on it that said, "Have a Great Valentine's Day" and told me she would take a raincheck on dinner--