say something like "goodbye i always valued your companionship" by text and then don't go on that messaging app for at least a week and then pretend to be one of your other friends or siblings and then tell the friend that ghosted you that your the other friend or your sibling and then tell the person who ghosted you that you committed suicide and see if they text back or respond to that. if they don't respond then forget about them, if they do respond then you send something like you were just kidding and that your not dead, then ask why they ghosted you. (this isn't really the greatest idea but it's something at least?)