The fear is understandable, but you are allowing it to spiral by feeding it. Most likely is that she's asleep. Use your DBT skills here.

That said, when she's better and you reconnect, you need to have a serious conversation with her about your need and rightful expectation for stability in your relationship. There are reasons why a therapy frame is important, and the haphazard arrangement you have with her isn't respecting that. In that sense, I believe she's being irresponsible. I think she can be of great help to you, but she needs to understand that stability and consistency is the foundation.