How to "unshare" a video in iCloud I shared a home video on my iPhone with myself via iCloud using my cell phone number. I was hoping that this would allow me to see the file somehow on my Mac but alas that did not work. I'm assuming this video is now using space on my iCloud account, so I'd like to "unshare" and delete it. How is this done?

Follow-up question, the video in question was added twice. I'm able to delete the videos as suggested in in the selected answer, however I'm now left with an empty stream that says "shared by (null)(null)". How do I get rid of that?
It appears that you've added a video to an iCloud Shared Photo Stream. Since you are the one that added it to the stream, you can delete it.


  Can I delete photos, videos and comments from a shared stream?
  
  Yes. If you are the owner of a shared stream, you can delete any photos, videos or comments that you or your contributors have added.


Source: Apple KB article: iCloud Photo Sharing FAQ

To delete a video from a shared stream:


Go to Photos → Shared.


Select the stream that you added the video to, then select the video.
Tap the Trash  icon to delete it.


To delete the entire shared stream:


Go to Photos → Shared.
Select the stream that you wish to delete.
Go to People → Delete Photo Stream.


With regard to your statement about using up iCloud storage…


  Do Shared Photo Streams use my iCloud storage?
  
  No. Photos uploaded to Shared Photo Streams do not count against your iCloud storage.


Source: Apple KB article: iCloud Photo Sharing FAQ