Bonnie and Jeremy (Steven R. McQueen) got together earlier this season but Graham told Zap2It that she does not think their romance will be easy.
"I wouldn't be surprised if there were obstacles," she said. "I mean, especially for Bonnie. She's just got some problems!"
However, Graham added: "I see it going really well for a while, and him really being a strong support system for her. And having that person that she can identify with that isn't going to make her feel alone. It's just familiar and a loving vibe."
Graham previously suggested that the couple could face some "heartbreak" in future episodes.
The Vampire Diaries returns for a new episode on Thursday at 8/7c on The CW in the US and on April 12 at 9pm on ITV2 in the UK.
Watch an extended trailer for the next episode of The Vampire Diaries below: