This is not another sad love song.
In 2008, the singer-songwriter, 50, was diagnosed with the autoimmune disease after collapsing while performing in Las Vegas. Although doctors initially thought it was a mild heart attack, she was later diagnosed with lupus, an autoimmune disease in which the body’s immune system mistakes healthy tissues as foreign invaders and attacks them rather than targeting the bad bacteria and viruses.
At the time of her diagnosis, Braxton, then married to musician Keri Lewis, had already formed a close bond with the Cash Money Records co-founder, 49. “He’s been my bestie for like 15 or 16 years,” Braxton tells PEOPLE in this week’s issue of the rapper. “He has come to my baby showers, my plays, my shows. I never thought we would be dating or getting married.”
It wasn’t until years later that he became her biggest support system, guiding the “Un-Break My Heart” singer through some of the hardest times in her life that came close to ending her career. Finding it “comforting to have someone tell you it’s okay to be ill and that you don’t have to be Wonder Woman at all times,” Braxton took their companionship out of the friend zone and hasn’t looked back.
“In 2016, I was doing a little tour just testing the market [to see] how far my endurance could go – and I got ill just before we went out,” Braxton says of the beginning of their relationship, when rumors first sparked after they were spotted getting cozy at the 2016 BET Awards.
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“Every day I had a show, he came,” she adds. “Every night he would ask me, ‘Are you okay? Are you good?’ I said, ‘Oh my God, he’s such a great guy!'” When Birdman finally made his move, “He told me he always liked me and I was like, ‘You never told me!’ And he’s like, ‘Well, you were married!’ He said, ‘I was always digging you.'”
Though battling a disease that involves the constant threat of blood clots and pulmonary embolisms can be mentally, physically and emotionally draining – especially with her musical comeback and trying to promote Sex & Cigarettes – Braxton says she never has to “fake” the state of her lupus around Birdman because he always “understands.”
“I can get on television when I’m having a terrible day and tell them it’s a good day, and he’ll say, ‘No, it’s not. I can tell,'” she says. “I’ve always had issues dating because I was ashamed to have lupus and felt like no one would want to take care of a woman with lupus – I was insecure. With him, I can be comfortable with a little hat or skully on with some lipstick and mascara, but I can just let my hair down a little bit and that feels great.”
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The pair first teased their engagement in February during a trailer of her family’s hit WeTV reality show Braxton Family Values, where she excitedly told her sisters, “I have an announcement to make — I’m engaged!” while flashing her canary yellow diamond ring that Birdman designed.
And with no time to waste, Braxton is already deep in wedding planning.
For more from Toni Braxton on her return to music, pick up our Beautiful issue when it hits newsstands on Friday and check out all of our coverage on PEOPLE.com.
“This is my second wedding and I’m over 40 – It’s like Carrie Bradshaw, the last bride over 40 – so I want something that’s elegant and a little sexy. I’ve already done the beautiful bell dress at my first wedding,” she says of the planned black, white and red affair. “This time, I want something that’s more vintage – ’20s and ’30s like Great Gatsby-themed.”
As for her groom’s must-list, “He said he wants macaroni and cheese. I said, ‘Can we have macaroni and cheese balls to keep it pretty?'” Braxton is letting Birdman have his say about the location — and for good reason. “He wants to get married in California,” says Braxton. “We talked about Atlanta, but he said no because he didn’t want any remnants of my first wedding.”
Wherever it is, Braxton says the event will be a family affair. “My sisters [including her youngest Tamar] will probably be bridesmaids,” says the singer, “and I’m going to have my dad give me away and my sons will meet him halfway and finish it. I’m excited about that.”