If you’ve spent any time on the "Cobra Kai" side of the internet lately, you know the rumors fly faster than a crane kick. Everyone wants to know the same thing: is Mary Mouser single? It’s a fair question. For years, the actress behind Samantha LaRusso kept her personal life under a pretty heavy lock and key.
But things changed. Big time.
Honestly, the answer isn’t a simple yes or no anymore because Mary recently dropped a bombshell that basically broke the fandom. If you’re still looking for her on dating apps, you’re about a year too late. She isn't just "off the market"—she’s officially planning a wedding.
The Massive 2025 Reveal: Is Mary Mouser Single?
To be blunt: No, Mary Mouser is not single. In February 2025, during the red carpet premiere for the Cobra Kai series finale, Mary and her long-time co-star Tanner Buchanan (who plays Robby Keene) did what fans call a "hard launch." They didn't just walk the carpet together; they confirmed they are engaged.
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It was a wild moment. They showed up, flashed matching gold rings, and even shared a kiss for the cameras. For a couple that spent years playing "just friends" in interviews, it was a massive shift. They followed it up with a joint Instagram post that basically said, "We're so happy to finally share that we're engaged."
They’ve been together way longer than people realized. Some fans who tracked their every move—like when Tanner threw Mary an Eras Tour-themed birthday party or when they were spotted at Disneyland Paris in 2022—had suspicions. Turns out, they were right. They were hiding a serious relationship for at least a few years to keep the focus on the show.
What Happened to Brett Pierce?
Before the Tanner news, everyone associated Mary with Brett Pierce. They were the "it" couple of her early Cobra Kai days. They started dating way back in 2015, long before the show even moved to Netflix.
- They met through mutual friends.
- Brett was her rock during her public battle with Type 1 diabetes.
- They used to post together constantly, especially on anniversaries.
But around 2020 or 2021, the trail went cold. No more photos. No more mentions. Fans noticed they still followed each other's families for a while, which led to a lot of "are they or aren't they" speculation. It seems they split quietly somewhere around late 2021 or early 2022. Neither of them ever did a big "we broke up" announcement, which is pretty typical for Mary. She’s always been low-key.
Why the Tanner Buchanan Romance Stayed Secret
Why hide it? Well, think about the show. In Cobra Kai, their characters, Sam and Robby, had a messy, complicated romance that eventually ended so they could be with other people (Miguel and Tory).
If the actors were dating in real life while the show was pushing different pairings, it could have been a distraction. Mary and Tanner seem to have prioritized the "Cobra Kai family" vibe. They wanted the series to end before they let the world into their private life.
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The Current Status in 2026
As of right now, in January 2026, Mary and Tanner are still very much together and deep into wedding planning. They’ve moved past the "secret" phase and now share glimpses of their life together more freely.
It’s a classic "friends to lovers" trope that actually happened in real life. Mary even joked about it on her Instagram Story after the engagement, saying "friends to lovers trope achieved."
Fast Facts About Mary's Relationship History
- Brett Pierce (2015–2021): A long-term relationship that lasted about six years.
- Tanner Buchanan (2022–Present): Started as close friends on set; officially engaged in Feb 2025.
- Current Status: Engaged and definitely not single.
Key Takeaways for Fans
If you're following Mary Mouser's journey, here is the real deal on how to stay updated without falling for clickbait.
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Keep an eye on her official Instagram. She’s much more active there now that the show is over. Also, don't expect a televised wedding; even though they've gone public, they both still value their privacy.
The biggest lesson here? Sometimes the "shipping" rumors are actually based on something real. While many co-stars are just friends, Mary and Tanner managed to build a lasting relationship while the world was busy watching them fight on screen.
If you're looking for the latest on her career or her advocacy for diabetes awareness, those are the areas where she's most vocal. As for her heart? It’s officially taken.
Next Steps to Stay Updated:
- Follow Mary Mouser and Tanner Buchanan on Instagram for their rare but sweet "couple" updates.
- Check out Mary’s YouTube channel where she occasionally talks about her personal life and health journey.
- Look for interviews from the 2025 Cobra Kai press tour to see the couple's first public comments about their engagement.