Reading the language used in these interviews, by Mr Markle himself, then seeing the behaviours and language his eldest children use, it just paints a picture of a very manipulative, emotionally abusive and cruel man. That 'she is who she's today because of him, she owes him because of that' and her getting her attitude from her mother, then trash talking Doria, Meghan, Harry, really anyone who has Meghan's best interest at heart, are huge red flags of abuse. Junior showed previously exactly similar behaviour in his attempts to blackmail Meghan, then humiliate her. Samantha has done that openly on her twitter and in her interviews. According to his own admission, Mr Markle used drugs to cope when Meghan was growing up. (interestingly, no articles picking this up, I can only imagine the headlines, had Doria admitted this...). It seems like, with all the estrangements, domestic abuse, pulling guns on people, alcohol and substance abuse, emotional abuse, that the Markle household was a horrible place to grow up in.
I think Meghan getting the role on Suits was a huge blessing in multiple ways, not just for her career. Her moving to Canada naturally brought a geographical distance that forced a longer separation between Meghan and the markles. I forgot who said it about Meghan, but they said, that after her divorce, Meghan simply flourished, she was free. Personally I don't think it was only about her divorce, I think she also began to flourish, because she was free from the abusive hold of the Markles.
I also think, that the distance healed the relationship between Meghan and her father a bit. The relationship was maintained mostly through phone calls and FaceTime. Meghan was away from the whole environment, and her dad couldn't play the same manipulative games with her. This wedding, and Mr Markle being initially big part of it, brought all the nasty back. I think there were a lot of last minute cancellations by Mr Markle when meetings were set up. I think he became again the same manipulative, self serving, and unreliable father he used to be. I don't think a lot of this behaviour is a surprise to Meghan, and i don't think her cutting him off was the first time. I just think this time Meghan has an actual healthier support system backing her up. Her husband is fully in her corner, her new in laws fully support her. For their own messiness, I think Meghan is for the first time seeing and feeling a much healthier family, and that is making her cutting her father out of her life much easier.