Matty Healy 'Quickly Fell in Love' with Fiancée Gabbriette Bechtel: 'Serious from Day One' (Exclusive Source)

Matty Healy and his fiancée Gabbriette Bechtel are happier than ever as they celebrate their engagement.

On Tuesday, June 11, the 1975 frontman, 35, and model, 26, announced their engagement after Bechtel shared photos of herself wearing her black diamond engagement ring.

An insider exclusively told PEOPLE that Healy and Bechtel are “in love” and thrilled to be engaged just nine months after they sparked dating rumors when they were spotted engaging in PDA in New York City in September.

"They’ve only dated since last fall, but Matty quickly fell in love with her," the source tells PEOPLE. "They've had a serious and intense relationship from day one."

"They’re excited to be engaged. They're such a cool couple," the insider adds. "They like to do things their way."

Following the news that Healy had popped the question, fans zeroed in on the former Nasty Cherry vocalist's non-traditional ring — the piece of bling features a large black gem surrounded by pavé diamonds around both the stone and band.

"The engagement ring is so her — it’s perfect. She's unconventional and fun," the source tells PEOPLE. "They are both close with their families. Everyone is happy for them."

Healy's mother, actress and TV host Denise Welch, addressed her son's engagement on the June 12 episode of British talk show Loose Women.

"I obviously have known for a few weeks that Matty got engaged ... They went over to see their friends Charli and George in New York [last night] and I woke up this morning to the fact they’ve put it on Instagram," Welch said.

"Instagram official ... he's got engaged to Gabriella Bechtel — Gabbriette she's known as. Black diamond; he had it made for her," she added. "I couldn't be more thrilled. We couldn't be happier — she is everything I would want in a daughter-in-law. I'm thrilled."

The "Charli" who Welch referred to is Brat musician Charli XCX, who got engaged to The 1975 drummer George Daniel in November.

Bechtel shared her Instagram engagement announcement from Charli's show in Brooklyn on Tuesday, captioning the post: "MARRYING THE 1975 IS VERY BRAT."

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Before the couple began dating, multiple sources in June 2023 confirmed to PEOPLE that Healy had ended his brief fling with superstar Taylor Swift. Gabbriette was most recently linked to fellow model Levi Dylan, son of Jakob Dylan and grandson of Bob Dylan.

Bechtel previously spoke with Homme Girls about how she and the musician had been trying to meet for years before they finally connected and began dating.

"He came to L.A. and we've been in love ever since," she told the magazine earlier this year.