I'm sorry you've had this experience. Maybe the other person was cut off or suddenly needed to go and couldn't say 'good-bye' properly.
It is most likely that it wasn't because of you but due to a distraction on their end.

I don't know why your dad said such a thing to you, but try not to let him define you. Family members sometimes say hurtful things and also make statements that are not true.

It's good you're here, Clouds_and_Sun! You are unique - always remember that. That's a good thing. Nobody can replace you. Hold on to that and treasure your individuality.