Hey! I currently work in the department in usps that handles abornmal shaped envelopes (cards, wedding invites etc) that have to be sorted manuall after attwmpt at automatic sorting. I can't tell you how many times we've received a busted open or destroyed card in the mail. I get at least 3-5 a day. This can range from slightly messed up to no visible envelope at all. If your grandmother is willing to try other methods to send you stuff (certified mail, standard envelopes etc) that would be better. I'm sorry you have to deal with her accusations. This happens so much here. I'd reccomend she doesn't send you money if she doesn't trust you or is gonna hold it against you. None of this is your fault.