Jennifer Lopez & Alex Rodriguez Are 'Soulmates Who Bring Out the Best in Each Other': Source

Jennifer Lopez is the “happiest she has ever been” with Alex Rodriguez, a source tells PEOPLE.

“They are incredible together. Very much soulmates that bring out the best in each other and are so supportive of each other,” the source says of the newly engaged couple.

“From the start, they moved very quickly. Their relationship was always very passionate. Jennifer quickly fell very hard for Alex. And she quickly started planning for the future,” the source says.

The source says that “there were talks about an engagement from early on,” but Lopez, 49, then “realized that she wanted to live more in the moment” and “enjoy what they have together with the kids.”

Lopez and ex-husband Marc Anthony, 50, have 11-year-old twins Maximilian “Max” David and Emme Maribel, while Rodriguez, 43, and ex-wife Cynthia Scurtis, 46, share daughters Ella, 10, and Natasha, 14.

The singer and the former MLB player announced their engagement news on Saturday, shortly after Rodriguez popped the question during the couple’s romantic getaway to the Bahamas.

“She said yes,” Rodriguez wrote alongside a photo of Lopez wearing her stunning diamond engagement ring. Sharing the same image, Lopez simply captioned the romantic snap with eight black heart emojis.

“Jennifer is ecstatic and so are their families and friends. Very few people knew Alex planned on proposing. It was very much a surprise for Jennifer,” the source tells PEOPLE. “It was just how Alex wanted it.”

Opening up to PEOPLE last December, Lopez shared that before finding love with Rodriguez, she had to do some real soul-searching to figure out why she seemed to repeat unhealthy patterns with men.

In the wake of her divorce from Anthony in 2014, Lopez said she was “done blaming other people — he did this or he did that — and I said to myself, no, it’s you.”

“Until I could really learn to be happy on my own and love myself, these relationships were never going to work out, no matter what. That was a big turning point for me,” said Lopez, who also worked with a therapist to help discover what makes her tick.

It was with a renewed sense of self — and with her priorities straight — that she began her relationship with Rodriguez in early 2017.

“It wasn’t until I met Alex that I felt like, ‘Okay, I can be in a relationship again,'” she said, adding that the pair “bring something to each other’s lives that is profound, good and healthy.”

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As for what he admires in Lopez, Rodriquez previously told PEOPLE “her best quality is undoubtedly her generosity.”

“I see it every day and my kids see it as well,” he said. “Jennifer has given so much to me and my kids over the last two years.”

Opening up about the pair’s blended family, he added, “Our kids have become best friends and that keeps us both grounded and appreciative.“

“We couldn’t have asked for anything better than the four of them getting along as they do,” he told PEOPLE.