What was her problem?

When my ex and i were together we always went to a local bar. There was older women there with her bf. She was flirting with her ex so her bf came over to talk to us. He said I was pretty a couple times and when she hung out with us he said it again. MY ex was pretty handsome. He was Dominican and white but he looked white towards me. I look spanish or mixed. Ive had a lot of people say i look better then the average women. And that im pretty cute, and have a unique look to me. After my ex and I broke up I went to the bar by myself. The same lady was there and she asked how I was and where was my bf. I told them that we broke up and she apologized. Then she started acting funny towards me and looked at me like I was up to something. She was being really awkward but still talked pleasantly. But I could tell she didn't want me around. Do you think it is because im hispanic blk and white? Maybe she is racist? OR do you think she thought I was a suspicious person who was going to try to steal her bf? Idk if she was jealous of me or wtf it was . But it really bothers me because I thought we were cool. THis happens a lot. People say I have a serious look but idk