Hopefully, law enforcement pulls cell tower records to identify any phones in her vicinity at the same time. That might answer the first question. I say might because if she was experiencing a delusion she might have been actively evading law enforcement (despite having called them) during any initial search. But she would have to go somewhere and be with someone now and that person or persons would have to know there is a search for her. The alternative, if she isn't with anyone, or was actually being pursued, is pretty bleak.
We haven't been given any information about her current living situation or what was going on with her during the hours or even day before to give us any kind of direction. We don't know if she was living on her own or with someone, where her kids were, if she was working, if she had another boyfriend, if she stopped taking medication or had recently switched medications (if she was on any), if there was an issue with child custody involving any of the fathers, if she has shady people she was hanging out with or new friends. Nothing.
We also haven't been told what was found in her car. So we don't know if she had taken some of her possessions, bags of clothes, for example, or perhaps some keepsakes that indicate she was "escaping" to somewhere. We don't know if her phone was found or her purse. How much money she may have had on her. Nothing.