How do you delete Facebook inbox messages so they don't appear in the receivers inbox?

Sorry buddy, the only way to delete them out of your friend's inbox is to ask your friend to delete them for you.

The only way to get over this is by using your friend account to delete the messages you want. If you deactivated your account, your friend will still have the messages but will not be able to click your name, your name will just be on black. If you're in trouble, I think you might want to "Change" your name, then deactivate the account. That might help your privacy for now.

Unless your friend deletes the messages from their inbox, the messages will always be there, the existence of your account will have no effect either way.

once you send them, their sent. you cant change it sorry, you can either go on their acccount and delete it or if you delete your fb, it will still be there but wont show youre name only facebook user.