Ex best friend still contacting me

So my best friend of 13 years and I decided to part ways about 2 years ago. I miss parts of the friendship but other parts had their toxic elements. She was always a very jealous person and had to be doing better than me or earning more money etc. We never deleted each other from Facebook, we just decided to go our seperate ways and not talk etc.

About a year after we stopped talking I had my second baby. She contacted me saying congratulations, which was nice and then we had some small talk and that was it, never spoke again. Fast forward another year later and we bought a house. She must of seen my husband post on Facebook because I got another text from her saying congratulations on the house. Again I texted back politely thank you and that was it.

2 weeks ago for Mother’s Day I put a happy Facebook post up with my kids in our new yard. She blocked me straight after that and I’m feeling confused.. why contact someone twice out of the blue and then days later block them? My husband and I rarely ever post to Facebook so it’s not like we would of been coming up in her feed constantly. I’m wondering if she’s jealous that I am finally very content in my life and it’s showing?