I want to store my file backups offsite, but not in the cloud since I am not comfortable storing certain personal and financial information in the cloud. I've decided to use an existing safe deposit box to store a hard drive that I will back up every few months. I do not need to back it up often because the data I am storing would not change very often.

What concerns me is the possibility that the contents of the safe deposit box will be lost/stolen, so I would like to implement some form of encryption. I am only recreationally good with computers/technology, so this is one of the areas where I am not knowledgeable.

A few relative notes:

• I would need something that I can do myself fairly easily, because I am new to it. But more importantly, it needs to be something my spouse (who is not great with technology) would be able to decrypt in the event I am not able to.
• I do not back up entire computers, only files/folders.
• I do not want to over-encrypt, but I am not sure a password protected folder or .dmg is sufficient.
• I have a Mac (I really don't know if this is relevant nowadays, but thought I would mention)

Any help would be appreciated! Thanks!