What does this mean?

Cara✨🏳️‍🌈 • 23yr old virgo queen
So my ex girlfriend just randomly messaged me in snapchat telling me how beautiful I am and that she didn't appreciate me when we were together. And I don't know how to feel because we're both in relationships currently. A few months ago we tried to rekindle our relationship and all of a sudden one day she texted me saying she was in a committed relationship and we would no longer be dating. I said okay fine but was slightly confused because I thought she wanted a relationship with me? We remained platonic friends and I even went over to her house last week and played with her pets and it was great fun. Now all of a sudden she's flirting with me at 2am? I'm definitely telling my girlfriend about this. What should I do?