My best friend is a girl who has cares very much about me. She considered me a brother and she was like a sister to me, and we called eachother bffs. See I have anxiety attacks, and since my friend realized that she said she'll always understand and she comforts me. One day I was having an attack and she was getting very uncomfortable, especially since I was crying (she was on her period). By the time I realized things were going to be bad, she wouldn't accept any of my apologizes, and she started ignoring me. A day later I told her I'm going to give her space, and asked if it's ok for her to message me when things are back to normal. She never replied. When I finally see her at school a couple days later, she's always turning away from me to avoid me. I messaged her saying "hey", but she never replied. This has happened to other friends of hers before, but she ends up making up with them, but they aren't as close after being ignored. I know she gets really moody during her periods, and if she holds grudges she won't let go of them once she's feeling better, so things get really difficult. What can I do to not be clingy, but have her come back so we can be best friends again?