Dove Cameron and Ryan McCartan met on April 3rd, 2013, at the set of "Liv and Maddie" a Disney TV show where they played a couple.
It was said that they didn't liked each other at first, since Dove didn't want to audition with Ryan because he kept glaring at her and giving everyone dirty looks. When they went into the audition room and did the scene "everything changed." Ryan took Dove's hand and looked deep into her eyes and suddenly they were both super into each other. Sometime later, the pair went on their first date. He took her out to dinner, frozen yogurt, and they went to this place in Hollywood called Bourgeois Pig and got some cider. He also took her to the Hollywood Hills. They began seeing each other around July 2013, but they made it official on August 6th, 2013. They got engaged in April 2016. They confirmed their engagement on April 14th, 2016.
However, they split up in early October 2016, after 3 years together. On October 5th, 2016, Ryan McCartan tweeted "Dove has decided this relationship isn't what she wants. We still love each other very much. Please be sensitive, as this is painful.", confirming their split.
Seems like Dove wasn't happy with him anymore, since she has said publicly to her fans on Instagram that Ryan was "terrible" to her while they were together and that she's more happier now that they are not together. However, Ryan has said that her claims about him are "gossip", so it is unknown what actually happened. The only thing we know is that Dove is the one who broke up with him, since it's something both has confirmed.