Is this girl trying to start drama with me and what's the point?

I'm a nutritionist and I work part time at a supplement store for extra income. I dated my ex for 4 yrs and we ended things amicably over 2 yrs ago. We don't speak, no drama, just moved on with our lives. We're both 33. He's now dating a 21 year old. I got several notifications on my phone that said this woman liked several of my photos on my public instagram account back in september and so I clicked on her profile which she probably expected I'd do. I saw a bunch of photos of her with my ex that said, "my lover, best boyfriend ever!" Okay so she got my attention and I wrote it off, didn't respond, didnt say anything, just thought she was immature. Now she has been coming into my work at the supplement shop and making small purchases and making it a point to tell my co-workers and any customers that will listen what her name is. She's forcing conversations and taking the lead so other people in the store will ask her questions and then she's volunteering information about herself that would hint she's dating my ex, she's saying it loudly so I'll hear. They met at work and work together. So she keeps reiterating to other people in the store where she works, what her name is, the fact that her boyfriend likes women with nice bodies so she's getting supplements etc. I know she knows who I am and that I work there part time, since she stalked me online. Now she's been coming in weekly putting on her show and I'm started to feel like she's trying to instigate. thoughts?