I killed my first two sourdoughs, too. The one I have now for nearly two years I got as a gift from an acquaintance. I had written in a discord server about me having killed the previous one with neglect and just offered to send me some of hers. For all the crazy people you meet via internet, there are others that are kind and friendly :)

FYI: you can make a "backup" of your sourdough in dry form. Just smear it on a big sheet of baking paper and let it dry - 36 to 48 hours, just to be sure it's really dry. Then break this layer in small parts. As a backup for yourself put it in a closed jar in a dry place. To send it to someone, put it in a Ziploc bag and you can mail it in a padded envelope.