Congrats on your sobriety! Stay strong. Some counseling with a therapist sounds like a good idea. That way, you can be very specific with your therapist and feel more secure that everything is confidential.
Your sister may believe that she is a victim. I can guarantee you that my sister has told all her church friends that I'm crazy and she is a victim. I'm thinking that therapists don't always get accurate information from their clients. Sometimes they might catch onto the fact that the client is the one with the problem, but that isn't likely always the case.
Here is a link to info. about Fear, Obligation and Guilt (FOG). I think you will relate to the situation:
https://bpdfamily.com/content/emotional-blackmail-fear-obligation-and-guilt-fogFacebook and social media in general can cause a lot of havoc in families. I'm glad I don't use Facebook. My therapist and I have briefly spoken about Facebook. It seems to be good for the therapy business,

You might want to coordinate with your brothers and husband in regard to Facebook strategy. Probably best to NOT respond to your sister's remarks, as it will fuel the flame. Might even restrict what your sister has access to or perhaps block her.
So sorry about the loss of your mom and your father's failing health. It appears to be common for personality flaws to appear when we have to work together on important things. The wheels fell off the bus for me when my sister and I had to start working together on issues regarding our parents. My Dad passed in Oct of 2014 and my mom in Feb. of 2015.
In our late teens and early 20's, my sister and I got along well. I just had no idea of things to come.
My sister's temperment changed over the years and boy was I surprised, when we were forced to work together and make a lot of tough decisions regarding our parents. After all, we were sisters and our parent's decline in health and death should bring us together, right? Boy, that couldn't be any farther from what happened.
My sister would hang up the phone in mid conversation. She argued about stupid things that were meaningless. She would pick a fight with herself and argue and defend a position before she would give me a chance to say I agreed with it. She was bad at listening, as she was always preparing for an argument and it was hard to get in a word in edgewise. She would say I said things that I didn't and then wouldn't acknowledge something I did say. In hindsight, I suspect she never heard a lot of things because she was so involved in preparing her argument instead of listening.
From her perspective, I was either talking down to her or talking over her head. If I deferred to her on a decision for the latest care facility, she told me I didn't care about our mom. If I had given an opinion, she would have fought about it. I just couldnt win. Then, she would go into violent rages.
I'm suspecting that your sister just wasn't listening when you called her about Steps 9 and 10. I guess people can react differently when someone is working their steps and ask for forgiveness. I received a forgiveness call in the past from someone I used to have a realtionship with. I had forgiven him on my own, long before the call. At that time, it bothered me a bit, as I had put the awful things I experienced with him behind me and I didn't want to rehash it.
Take care of yourself! You worked hard for your sobriety. Click around this website, as there is a lot of helpful information in the Learning Center and there are some links on the right side of the page.
I'm still on a bit of a learning curve myself. I'm sure others will have something useful to add for you.