I have been trying to talk to one of my old friends from high school periodically. I was messaging them just to check in with them to see how are they doing, or how have they been lately. They just don't message me back and perhaps all I see is the read or seen receipts under my messages I delivered before. Maybe they're too busy to message me back. In those cases they'll probably message me back later. Or they would read my message and then they'll not message me back, or ignoring my messages like they are not in the mood for a full conversation with me. Or even worse, they are not interested with me and don't want to be friends with me anymore, they rather be more close to the friends they have now. Its really hard for me to feel about losing one of my old friends I really missed for years. Its even harder to make new friends these days, and replacing them as one of my old friends and its just no use. And it kills my self esteem.