She might be a bit shy or hesitant to follow you directly. Watching your story allows her to keep up with what you're doing in a more low - key way. For example, she could be someone who doesn't want to seem too eager, so she opts for just viewing the stories instead of hitting that follow button.
There could also be other reasons. Perhaps she has her own privacy concerns. By only watching your story, she can get a glimpse into your life without being too involved. Also, she might be in a situation where she doesn't want to add more people to her following list, but still finds your story interesting enough to watch regularly.
Maybe she's just casually interested in your story content without wanting to fully follow you. It could be that she enjoys the specific things you post in your story but doesn't want to commit to following your whole profile.
It might be that she is shy about following you. She could be interested in you or what you post, but for some reason, she doesn't feel comfortable with the idea of following. So, she just watches the stories as a way to keep in touch without making it too obvious. For example, she might be worried about what others would think if she followed you.
It could mean she's just casually interested in your content. Maybe she doesn't want to commit to following you but still enjoys seeing what you post from time to time.
It could mean that they still have some interest in your life but don't want to be too obvious by following you. Maybe they are just curious about what you're up to without fully committing to reconnecting.
It could mean that they're still curious about your life. Maybe they're not ready to fully let go yet, but also don't want the commitment of following you.
It could mean she's still interested in you but is shy or doesn't know how to start a conversation. Maybe she enjoys getting updates from your stories without the pressure of direct interaction.
I don't think you should be overly concerned. It could be that she's just exploring different people's stories and yours caught her eye. There's no real indication that there's anything negative going on just from her not following but watching your story. In fact, she might eventually decide to follow you if she continues to be interested in your stories over time.
It could mean that they still have some level of curiosity about your life. Maybe they're not ready to completely let go, but also don't want to fully engage by following you. It's like they want a little peek into what you're up to without making it obvious that they're interested.
Maybe he's just casually interested in your stories without wanting to fully follow you. He might not want to seem too eager or committed by following.
There's a possibility that he's just casually browsing. He might not follow a lot of people but still checks out interesting stories when they pop up. Another reason could be that he doesn't want to be inundated with all of your posts in his feed if he were to follow you, but likes the quick and ephemeral nature of stories.
You don't really need to overreact. Just keep posting your stories as you normally would. If you're interested in her, you could try to make your stories more engaging, but don't be pushy.