But... Being an adult means you know the moment you send a photo out it's out.

There is zero reason to panic with a cloud. Saving. Whatever. It is out. And if you are so traumatized that you are on discord crying picking photos..

Perhaps neither of you are ready for that level of technological exchange. You are never safe in the world of pictures be they on the cloud or phone or printed. Think before you do. And if you really love someone don't hurt them because you wanna keep something they already sent to you on an unsecured platform by talking about how you messed up. Just save your stuff and move on. It's not hiding. You didn't sell her photo or post it. You didn't open it to the masses any more than her sending it did.