The fatal flaw in Abbie's relationship with Matt? She didn't get along with the best friend.

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There was a very specific moment on last night’s Bachelor finale when we knew Abbie Chatfield wouldn’t be Matt Agnew’s final pick. It lasted barely a few seconds.

But that was it. She was done. Nail in the proverbial coffin. Last bloom off the rose. etc. etc. Send in Osher, because [whispers earnestly] Abbie, it’s time to say goodbye.

The 23-year-old wasn’t even there when it happened.

It was the moment when Matt told his best friend, Kate, who would be in the final two. “So, there’s Chelsie,” he said, without hesitation.

And then this happened:

Note: the relative position of Matt's eyebrows to his hairline, the tiny twitch in the right one just after he said her name.

This was a man who knew how that news was going to be received.

Because though Abbie has developed a large and loyal fan base during her time on the show, she never managed to win over the person whose opinion mattered most.

In the absence of an appearance from Matt's family, Kate was the last line of defence between him and potential heartbreak.

And she wasn't keen on letting Australia's most famous Gemini through. She voiced concerns about Abbie's age, mismatched aspirations and how she would fit into their friendship group.

During their one-on-one chat, she posed questions like, "What do you think you have in common with Matt?" and raised suspicions off-camera about her authenticity ("What she's saying, I'm really not believing it.").

To Abbie, Kate's approach seemed "possessive". To Abbie, she was "horrible".

But for those of us watching from the security of our loungerooms, it was clear that a relationship been Matt and Abbie would have led to far more hurt than could come from a few pointed questions egged on by drama-hungry producers.

Flash forward a few months and years, and you can almost see the fights between the three of them. The awkward dinners and pub drinks, sitting at opposite corners of the table. Each declaring that they'd already tried making an effort with the other. One important relationship tugging just that little bit too hard on the other, until...

Because we've all been there, or at least somewhere nearby. We've been an Abbie and felt that hurt, that desperation to be part of your new partner's life, to find new friends in theirs. And we've been a Kate, the fierce protector, knowing you'll be the one to pick up the pieces if — or likely when — it all breaks.

Each position is as fraught and painful as the other.

But being a Matt is even more so. In the middle, the link in all the conflict, knowing one side will come undone if it continues. Maybe even both.

Last night we saw the moment this all ran through Matt Agnew's mind. It barely lasted a few seconds.

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