The Truth About Diem Brown's Relationship with Chris 'CT' Tamburello

The reality star "had room to love a lot of people," says a close friend

Photo: Mike Coppola/Getty

During her seven seasons on MTV's The Challenge, Diem Brown became a breakout star thanks to her competitive drive, warm charisma and signature hair-flip that showed off her feisty playfulness.

Along the way, fans of the series also began rooting for her romance with fellow castmate Chris "CT" Tamburello, whom she first clicked with on 2006's The Duel. With his bad-boy persona and her girl-next-door vibe, the pair often seemed like opposites — even as their chemistry was clear to viewers.

In the days since Brown's death on Friday at age 34 following a long cancer battle, many fans have wondered whether she and Tamburello, also 34, were still an item.

The short answer: no. Close friends tell PEOPLE the late reality star and cancer activist was single when she died, and Brown herself told PEOPLE in early October that she was unattached.

Still, friends say she and Tamburello always had a connection.

"Diem had such a big heart that she had room to love a lot of people, and he was one of them," her longtime friend Alicia Quarles tells PEOPLE in this week's issue.

On Wednesday, he shared an Instagram tribute to her, writing, "You have always been My Angel … We've been thru so much together over the years … Our plan to be together hasn't changed … it's just going to take a little longer now."

The photo showed a rosary, along with a photo of "Danielle Brown" (Diem's given name) and a ring.

"I'm going to hold onto this ring for you till we are together again," he wrote, calling her "The Love of My Life. My reason to be a better man."

A source says Tamburello was among those who spent time with her in her final days, but contrary to reports, he was not in the room when she died. The source also says reports that she accepted a proposal from him in the hospital are untrue: "They were clearly not engaged."

The MTV star had previously shared several other Instagrams about Brown, including one from her bedside earlier this fall with the caption, "Sometimes just being there for someone can be the difference between a good and bad day."

Tamburello was among the Challenge castmates who attended Brown's emotional funeral on Tuesday, where friends and family remembered her as a "dancing angel" and requested that in lieu of gifts, donations be made to her health advocacy charity, MedGift.

For much more from friends and family members about Diem Brown's cancer battle, along with personal photos, see the newest issue of PEOPLE, on newsstands Friday.

Editor's note: While there have been numerous conflicting reports about Diem Brown's age, PEOPLE has been able to confirm, via public records and with family and friends, that she was born in 1980 and was 34 years old at the time of her death.