It means what I think it means.  It's normal for URL to be used that way when referring to a Tumblr blog.  No one ever says username on there, or handle, but her Instagram handle is something different.  The other blog she has, off of Tumblr, is just Fitforafemme.com which is the whole URL.  Her Instagram handle is something different, but her blogs are both fitforafemme.  But, no one ever says "Oh, you have a blog, what's your username?"  It's always called a URL.