I can't stop the flooding tears!

I’m sitting here now, and tears are flooding down my cheeks. I wonder if any of you ever suffered so greatly when you moved to highschool. In primary, I had a real friend from grade 3-6 we told each other everything! She was my only comfort, she was kind of like the missing peice in my life, or the glue holding me together. On my first day of highschool, 6 weeks ago, I figured out she was not in my class. Now we don’t play with each other anymore, because I never find her, but even when I do, she’s playing with her other friends, from her class, and I’m too shy to come up to her and her new friends, incase they think im weird, or they hate me or something. And when I do get the courage to come to her, I say hi, sit down next to her, and her friends, and she simply says, ‘hi” and shortly afterwards, “bye” we’ve always been such close friends, and she was my only real friend, the one I can trust and rely on, and I feel like my whole world is crumbling, I know I need to talk to her, but I don’t know when to start, and I know I need to let go, which is what I’ve been doing ever since, but I’m starting to feel so lost now… Please help! I can”t stop the tears!