Fear of rejection is holding me back from messaging her, what should I do?

Long story short, I was with my first love for 3 years before we broke up nearly 10 years ago. We were young and in our early 20s back then, things just fizzled out.

I've always thought about her but eventually we went our separate ways, she got in to a relationship with another guy for a few years but eventually he ended up cheating on her, this was around 2017. At the start of 2019, she did add me on social media but she didn't say anything to me so a few days later I ended up deleting her because I realised I still wasn't over her.

At the end of 2019 I heard that she was engaged, she ended up getting married but then I heard she got divorced around a year and a half ago. A few weeks ago I found out that the reason for her divorce was because her husband cheated on her and was abusive towards her.

As for me I have been single for a few years now, I have been evolving in my career and proud of how far I've come and have recently started a new chapter in my career. I considered getting in touch with her a few months ago but I noticed that she had cut off a lot of people from her social media so I wasnt too sure how she'd react to me adding her, I thought she'd reject me seen as she's cutting off a lot of people.

So 3 weeks ago I took the plunge seen as I had nothing to lose and sent her a request on instagram, and she has accepted and also followed me back. She's been viewing my stories and today I posted a life quite on my story which she liked, I haven't spoke to her yet. I liked one of her posts a few days ago.

I'm tempted to send her a message but not sure if she'll respond or how she'd react, I was hoping she'd message me first but don't think she will and I want to tread very carefully with her as I don't really know where her mind is given what she's been through. I know I may be overthinking it but any advice would be appreciated, thanks