Hi @ryane217!
Welcome to the AT&T Community Forums! I am sorry that you and your girlfriend are being harassed by whoever is sending the text. This is one of those things that is hard to stop from happening, especially if they spoofing the number.
You can attempt to block the message by pressing and holding down the received text. A sub menu should come up and allow you to block the sender. Again, if they are spoofing the number, that won’t work. The only resolution at that point would be to change the phone number.
Thank you for joining the AT&T Community Forums!
Kevin, AT&T Community Specialist