Why do childhood friends grow apart? My best friends of almost 12 years dumped me because of a fall out?

They haven’t spoken to me since last month and it’s been almost two months….let’s just say we had a fallout and we’re no longer friends. We’ve been out of high school for a year and I thought as children we would be friends forever. I tried contacting them this week again but they refuse to speak to be because of my “toxic” ways. I apologized so many times and they refuse to reconnect. I want my besties back! 😭😭😭😭💔💔💔💔