Preface: Sorry about this wall of text.
There is a girl that know from having a class with her last school year, and back in November I decided I wanted to be friends with her again. Barring extra details that would be too much to explain, after a very awkward conversation due to the fact that (I presume) she thought I was looking for a bf/gf relationship, we decided on "simply being friends". It was alright for a while, but due to me now not having a class with her, I would only really be saying Hi in the hallway or the rare 5-minute chat.
Then at one point my grades (marks) took a steep drop and I abandoned almost all social activity and focused on fixing them. She eventually asked what was going on and I explained exactly that. After I had my grades at a manageable level, I began talking to her again. When that happened also lined up with when our school did our annual Musical. I was a cast and she was a stagehand, and being near each other let us talk a lot more than we usually do. I inevitably unloaded a lot of personal stuff onto her, which I really regret doing, and at one point she explained that she liked a friend of mine. She asked if "[He] would still be [her] friend after the musical ended?", and I, incorrectly, predicted Yes.
After the musical did end, our connection was really weak, and come 2 weeks after we didn't talk at all. All of the evidence I have regarding that could have caused this is very conflicting and I cant find one single solution. I feel extremely compelled to apologize to her, but I'm not sure if it's the best idea to begin with, as this depends on whats actually going on.
Case 1 - She simply forgot about me. As opposed to the first time, she hasn't asked me about whats going on. She could just be occupied with grades of her own or simply involved in her own life. If this is the case I don't want to apologize, as it would come out of nowhere and just result in me butting into her life which I don't want to do.
Case 2 - After having to lose being friends with the friend of mine, and due to me practically treating her like a therapist (that's probably me over-exaggerating), she doesn't want to have anything to do with me. Over time I have noticed telltale signs that she might have never wanted to be friends with me in the first place, she being friends with me maybe out of pity, or maybe something else. I would want to apologize, but I don't want to seem like I'm apologizing for attention or anything like that.
Case 3 - Shes in my situation. She has no clue what is going on, and might think herself that I don't want to be friends with her. I find this odd due to how I made the proposition in the first place, but considering how much "logical hopscotch" my mind likes to play when thinking about my social relationships, I feel like this still is a possibility. In this case if I did apologize, it may be awkward, but I don't believe it would harm anything, and I would want to do so.
I am really troubled about all of this and its shown in the last few days. I've been asked if I was alright a lot recently so obviously something is showing. After thinking about it this long and being unable to draw any conclusion myself, I turn to ask people who aren't totally socially inept for advice. If you want to ask about something else I don't at all mind. Ill talk about any extra information.
Thanks for reading. Any help appreciated.