Wesley, 34, and Tonkin, 27, who were last seen in public together on Dec. 20, first met on the set of The Vampire Diaries in 2012, and started dating the following summer. Tonkin had a recurring role on the fourth season of the CW hit, before her character joined The Originals spin off in 2013.
"They are still good friends. The relationship just ran its course," a source tells E! News, who was first to break the news.
ET has reached out to Wesley and Tonkin's reps for comment.
Wesley spoke to ET about sharing his first scene with Tonkin on The Vampire Diaries last year, describing the experience as "cool" and "nice."
"It was crazy, I had never worked with her before. It was very funny, we talked about it, but we literally never rehearsed [the scene] or ran it. We just said, 'Let's just do it when we get to set,' because otherwise it would just be awkward, and it was cool. It actually wasn't in the least bit uncomfortable or awkward," he recalled. "It was just kind of like we just did it and we were both in it and we both committed to it. It was nice, it was funny."
The series finale of The Vampire Diaries airs this Friday. See more on in the video below.