Raven and Adam are clearly happy with each other, but she noted "it's hard to say" what makes their connection so solid.
"I have definitely been in horrible unhealthy relationships," Raven admitted. "I think it depends on self maturity [and] growth."
The former The Bachelor bachelorette added, "Also, some people can either bring out the best or the worst. Adam brings out the best in me that I've never had before. IDK if he should take credit for that or myself for growing into that."
Prior to meeting Adam in Mexico on Bachelor in Paradise, she finished as the runner-up on Nick Viall's edition of The Bachelor behind winner Vanessa Grimaldi. (Nick and Vanessa split just five months after the March 2017 finale aired).
As for Adam, he competed on Rachel Lindsay's season of The Bachelorette, Season 13. He was eliminated, however, after Rachel's round of hometown dates.
"They were at a wedding in Arkansas together last weekend and they kept telling friends than an engagement is coming soon. It just seems like the next step because things are going so smoothly," the source said.
And Raven -- an Arkansas native and boutique owner -- shared on Instagram in July 2018 she and Adam live together in Dallas, TX.
"Adam is my favorite person. I'm thankful he is the man he is. He sets an example for how every man should treat a woman," Raven wrote on Instagram at the time.
"Don't get me wrong he puts me in my place, but he also loves every bit of me. I don't think I could love him more, but I continue to fall more in love with him every day."