Friend list was originally designed so that both players can keep their track and freely communicate. If something like accident happens, then it's that person's fault.. However, if you delete someone for a reason that you hate that player, especially in OP case. You might want to block that person, and only in that situation, It's completely justified that the other person will no longer see your name on friend list. But I don't think deleting someone from the list should automatically separate both players - and there are many reasons for that.