Sorry to hear that, OP :( Sounds similar to my then situation and, ugh, that kind of situation can mess up your psyche in the long run.

Your dad sounds narcissistic and it's sad that he's at that stage in life but he's still immature (especially with that FB stint). It might be hard but, have you and your sister talked to your parents about how it affects the two of you? And, if possible, request for them to undergo marriage counseling? If he actually cared about his family, he'll at least try to change something, none of that empty "alam jong ako yung may kasalanan" bs, kasi hindi lang naman silang mag-asawa yung naapektuhan, pati kayo ding anak.

Also, just a sidenote, it's best to keep in mind R.A. 9262/VAWC. What your dad is doing falls under psychological violence. Legit, if elementary me knew that, I would've slapped that to my dad's face for all the distress that he caused the family.

P.S Bobo nung isang comment dito, nakak-urat haha