The Duchess of Sussex told her father he had "broken [her] heart into a million pieces" for causing her "unnecessary and unwarranted pain" in an emotional letter.
Meghan, 37, wrote a five-page note to Thomas Markle last August in which she complained he had made no attempt to contact her and expressed his displeasure at him for giving interviews claiming he had been shunned.
She also let it known how hurt she was at her feeling he had sided with her half-sister Samantha Markle over her "vicious lies".
Thomas said he wanted to keep the letter private "out of respect" for his daughter, but has now made it public following recent reports about its contents.
In one extract, obtained by the Mail on Sunday newspaper, Meghan questions why he told the media he had been in touch to tell her wouldn't be attending her and Harry's wedding after suffering a heart attack because she didn't receive a call from him.
But he told the publication: "I sent Meg and Harry a text telling them I wasn't coming. It was too dangerous after my heart attacks."
I thought it would be an olive branch. Instead, it was a dagger to the heart.
The former Suits actress went on to discuss how "horrifying" it was to learn about his heart attack from external sources.
She wrote: "I have only ever loved, protected and defended you, offered whatever financial support I could, worried about your health... and always asking how I could help.
"So the week of the wedding to hear about you having a heart attack through a tabloid was horrifying."
Adding she begged her dad to accept help, the retired lighting director again defended himself from Meghan's claims.
He said the couple "knew what was going on".
Meghan also hit out at her father for publicly criticising Harry, despite the prince being "nothing but patient, kind and understanding" and begged him to stop "exploiting" their relationship and "fabricating" stories.
And she also insisted Thomas had done nothing to try and get in touch with her since the week of their wedding, despite his public claims she had rejected his attempts.
Thomas, 74, branded Meghan's lengthy letter a "dagger to the heart" and dismissed her claims, showing the newspaper texts he believes prove he'd made attempts to communicate with his pregnant daughter and her spouse.
He said: "I thought it would be an olive branch. Instead, it was a dagger to the heart."
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