Despite a strong start and an early date which included a safari in Botswana, it wasn't all roses for the couple and Harry doesn't shy away from one of their early challenges: their first big row.
Harry admits in his memoir that he spoke to Meghan "cruelly" on evening in December 2016, just a month after he had released an unprecedented statement defending his new partner against "abuse and harassment" in the press and online.
The evening began well, he writes, with Meghan teaching Harry how to roast a chicken while James Taylor and Nina Simone songs acted as the soundtrack to the "quiet night" and Harry opened some wine.
However, things quickly deteriorated after Harry became "touchy".
"Maybe the wine went to my head," he wrote. "Maybe the weeks of battling the press had worn me down. For some reason, when the conversation took an unexpected turn, I became touchy. Then angry. Disproportionately, sloppily angry."
Harry went on to explain that Meghan took a comment he made "the wrong way" because of the "cultural difference" between them, which led to him to speak to her "harshly – cruelly".
"Meg said something I took the wrong way. It was partly a cultural difference, partly a language barrier, but I was also just over-sensitive that night. I thought: Why’s she having a go at me? I snapped at her, spoke to her harshly – cruelly.
"As the words left my mouth, I could feel everything in the room come to a stop. The gravy stopped bubbling, the molecules of air stopped orbiting. Even Nina Simone seemed to pause. Meg walked out of the room, disappearing for a full fifteen minutes."
Harry then went upstairs, where he found Meghan sitting calmly in the bedroom. She then told him "she would never stand for being spoken to like that" and asked him where his anger had "come from".
"Where did you ever hear a man speak like that to a woman?" Harry says Meghan asked him. "Did you overhear adults speak that way when you were growing up? I cleared my throat, looked away. Yes.
"She wasn’t going to tolerate that kind of partner. Or co-parent. That kind of life. She wasn’t going to raise children in an atmosphere of anger or disrespect. She laid it all out, super-clear. We both knew my anger hadn’t been caused by anything to do with our conversation."
Meghan then encouraged Harry to find a new therapist, something that he says he had tried before at his brother William's recommendation, but had "never found the right person".
Harry also details in Spare some of the sessions he undertook with his therapist and the revelations they came through whilst working together.
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