Sharing Our Innermost Thoughts

Sooo I have this so called best friend of mine, we’ve known each other for 5years now and we became really close 4 years ago.
So thing was that she was part of a popular group which was very toxic and I was her non toxic private friend. We always hung out a lot but no one really knew that we were bffs. I was okay with it back then, I was understanding.
However now, we’re both in the same college and things look like they’re the same but it’s changed. She treats me like a bff when we’re in private. But in front of everyone someone else (my other friend is her bff) no one really knows how close we are/how we used to be. Worst is that now she only contacts me when she needs help with studies. Everyone knows how the bond with your bff is like. She never treats me like a bff but still calls me one. She never shares her feelings, thoughts secrets. I always find out abt it through a 3rd person. Hell she didn’t even tell me she got a tattoo which is like a pretty big thing here. I hate it, what is it that I don’t have to become her bff. I don’t expect much from her, I don’t expect us to hang out all the time. But just casual convos?sharing your feelings? Is it too much to ask for?