Backstory. I am a fully grown adult. I haven't seen my dad in over a decade. He was exceptionally abusive, an alcoholic and all round terrible human.
He has a partner, long term. Very odd woman, clearly also an alcoholic however appears to be functioning. She's lost all her family due to her relationship with him (so my grandma, his mum, says). Ive never met his girlfriend.
Years ago my sister found her social media. Call me odd but I was compelled to look. It became apparent that she had been posting (indirectly) about me and my siblings. All of it total nonsense but some times she seems to find out elements of things and some things I have no clue how she would know. She posts on social media multiple times a day.
Its obsessive.
How do I deal with it?