Alyssa lost her best friend. She didn't lose her in a supermarket. She didn't lose touch with her.
Alyssa has truly lost her best friend. There is no way to contact her on the other side, and it was all Alyssa's fault.
"Why? You don't even know him."
"You don't even know me."
"You barely know him, Cassie!"
"You barely know me."
They went from barely knowing each other to falling in love.