UPDATE: @taconator informed me the "binary wallet file" backup option is probably irrelevant when using the "Cloud Model", as it's probably just saving the local wallet, whether it's currently being used or not.

Also, additional feedback seems to indicate that this problem seems more likely to effect users of the browser-based wallet. If you are using the "Wallet Model", and the browser cache is cleared or becomes corrupted for some reason (either manually or automatically), and you have not backed up your binary wallet file and/or your private keys, you WILL lose access to your account!

This would, of course, imply that @lindahas was most likely using the "Wallet Model" in the browser. As mentioned previously, be sure to back up your binary wallet file, your private keys, and your brain key. This advice may be even more prescient if you're using the browser version of a bitshares wallet!

If you're looking for a safe way to protect your keys and passwords, one terrific open-source option is KeePass. Be aware that KeePass doesn't automatically save changes you make back to its database, so make sure you hit ctrl+S after making changes to persist them to the drive. There are some options you can set to do this more automatically, however. To understand more about those options, you can visit this sourceforge thread.

And if you need a solution to encrypt and protect your key files stored in the cloud or on a USB stick, check out another great open-source project, Cryptomator.