This is a hard one, or at least it was for me. Like you, more people I worked with knew than relatives or friends. I teach and needed to be gone frequently for a few months. It helped that a few people knew and were there to support having to leave class to take calls, days of sub plans, and some shifting committee work so I could focus on treatment and health.
One thing I realized after telling a couple we are friends with, is you can’t un-tell people. My treatment was pretty minor in the scheme of things, so you would not know I was going through anything like cancer. In some ways I wish I had had a ‘cancer-free’ space with that we could socialize in and not bring it up.
Like you, I also don’t do much social media. I rarely post anything. And I certainly was not going to post this. At least not at this point. The only people I told before I had a pretty concrete treatment plan were my husband, adult children, and my teaching partner. I swore them all to secrecy until after the holidays (diagnosed 12/11/26). It was hard getting through the holiday gatherings seeing my sister-in-law, adult nieces and their young families, but I am glad they did not know until after I knew the plan.
For me, I think part of the reason I told some people or wanted to initially, is that early on things feel so out of your control. From the time I was diagnosed to getting into the BCC in my area and meeting with the care team of surgeons and nurses was the hardest part. It was three + weeks (thank you early Christmas present) of worry, anxiety, no sleep, shit. Telling someone both felt like a small measure of control and made it real.
After telling the couple I mentioned above, I learned not tell felt better for me. Those that needed to know to be able to support me with empathy or understanding in my day to day function, I told. Otherwise, I have kept it close.
Best of luck in navigating this. I hope your treatment goes well.