It could help to ask yourself if your friend has changed — or if your expectations have changed. If your friend doesn’t usually initiate frequent contact, then it could be that her behavior is the same as it always has been, but your expectations of her have changed. She could be giving you space. She could also be having difficulties of her own. In your place, I’d reach out and ask clearly for what I wanted, and see what her response might be.
As others have noted, many of us have been under quite a lot of stresses of multiple kinds, for a very long time. I’m not even clear from your post that she’s “disappeared “, since you haven’t given a timeline and have indicated that you don’t “need” anything, but would appreciate a check-in. In your place, I’d reach out to my friend, see how she’s doing, and let her know how much I value keeping in touch. If you haven’t had this type of conversation, then it’s quite possible that clearly communicating your current needs might easily get you the caring attention and connections that you would like.
Although you say that you would never disappear on a friend like that, if you haven’t reached out to her either, then you have no way of knowing how she is experiencing this relative lack of contact.
I’m not suggesting that you should reveal more details OP, but if your friend clearly knows that you’re in distress, would like to connect, and it’s been weeks or even months beyond your usual types of connections, my take on this would be different vs. realizing that your expectations have changed in ways that you haven’t clearly communicated to your friend over the course of a relatively short period of time.
tldr: Does your friend know that you’d like her to reach out?