I think im losing my friend, what can I do?

So I worked at a big grocery store- and one of the other girls in my department was a good friend of mine. We would get together outside of work and hang out and we always had so much fun together.Well I left the store for a better job a week or so ago after finally getting fed up with being treated like crap by managment and the the drama between me and my immediate supervisor. For like 2 weeks before I left and now she has been acting kind of funny and uncomfortable. My mom was in the store shopping and she said she loves my mom so she always visits with her but even my mom said she was acting kind of uncomfortablr. I can't think of anything i did wrong but i feel like she doesn't want to be friend anymore and i'' not sure what to do. I tried texting her yesterday to try to get together but she never answered so im at a loss of what to do