Need help understanding this girl

So I’ve been talking to this girl I met on here for almost 2 months. It started as just snap chatting but then we got to be each others #1 best friend and still are. We fall asleep on video calls every night and it’s the best thing ever. I enjoy spending time with her a lot, she’s exactly my type, and I’m 90 percent sure she feels the same way. Just for context, we don’t live near each other at all, and I am 24, she is 21.

Where I started getting anxious is after waking up on a call like we usually do I for whatever reason just asked her if she was talking to any other guys and to my surprise she said yes which honestly made me feel like shit. She said they don’t do anything sexual, and that they only talk once or twice a day, and that they flirt sometimes. She said she didn’t want anything serious, but obviously with the way things are going, I am doubting that. I also made it clear when we started talking that I don’t like talking to multiple people at once, and she agreed. I did appreciate her honesty, but I truly was expecting her to say no.

Now whenever we aren’t on a call I’m thinking “is she on a call with the other guy?” Or “she’s probably talking to him rn”so I am anxious asf whenever we aren’t physically speaking.

I really am starting to like this girl, and I don’t wanna be an option to her. Can anyone(preferably a female that can help me understand her perspective) help me understand what she might be thinking or how I should go about this situation? I asked her that roughly a week ago and I’m hoping she’s stopped because we are usually on a call anywhere from 15-19 hours a day, and we text in between them. I don’t see how she’d even have the time to talk to other guys. She works a job that isn’t consistent so she isn’t working right now but still, we are basically talking 24/7.