Do you people out there actually still have any decency? Do they know that rejection can leave very deep physical scars just like abuse too?
Rejection and ignoring someone for no reason is plain rude, and shows lack of character. It can damage someone pretty good too. Don’t promise to keep in touch or pretend to be very keen on someone when you aren’t as not acting upon your words can cause as much psychological damage as actual abuse.
THINK before you act!
Also if someone takes the time to write to you and it’s a kind or helpful letter / e-mail / message, take the time to at least reply, even if it is only one sentence, at least thank them for contacting you!
The only time it is actually best and okay to ignore someone is when they are being rude, or clearly just wants to start / cause drama. No need to feed the bullies and trolls with the wrong sort of attention they seek, ever.