When you are at her house log on to FB and let her see for herself. Post some sort of comment like "hangin with XXX". Then when she is logged on help her by going to her wall and making sure she has the correct stuff clicked on when she hovers the mouse over your name.
Hover the mouse, while logged on her account not yours, over your name and when the box comes up move the cursor down to the word friends.
Make sure it is clicked on "show in newsfeed".
After that is clicked go to "settings".
In the top half of the box she can choose to see "All updates", "Most updates", or "Only important updates". I choose "All updates" for my close friends. I use most updates for everyone else.
In the bottom half I unclick on everything except "status updates" because I usually don't want to see every picture my friends make a comment on, nor do I want to see every game post they make on games I don't play, nor do I want to see every single comment they make on their friends walls or posts. The only one I really want is to see what they have to say about what they personally are posting.
I found that my wall would suddenly be filled with my friends comments on their friends posts and if their friends posted pictures of their kids then those pictures would show up on my wall with all their friends comments and posts. It was crazy. I found that by not clicking that I wanted to see my friends posts on their other friends posts I was much happier and able to manage my own wall.
I do click "Games" if I play games with that person so that anytime they post a game bonus or request I will see that post.
Other than that I do have a couple of younger cousins that like alternative music from what I like so I have their boxes clicked to show "music and videos". I like to see what else is out there that I don't know about in music. I learn a lot from these kiddo's.
Just go on her wall, search for your name in the search box, when it comes up then adjust the settings so she can see you. This way it will also show her that you don't have her blocked, she may have her settings to not show you.