Robert Pattinson and Kristen Stewart
Robert Pattinson (R) and Kristen Stewart pose for pictures before the German premiere of The Twilight Saga: Breaking Dawn Part 2 in Berlin, November 16, 2012 Reuters

American actress Kristen Stewart reportedly misses her former boyfriend Robert Pattinson, who is dating Suki Waterhouse. The Twilight actress apparently reminisces the good time the two had together.

Adding on, Stewart also is reportedly heartbroken over news that Pattinson is dating Suki Waterhouse. A source told Hollywood Life: "Kristen sometimes struggles with regret when she thinks about her relationship with Rob."

"Her feelings about how things ended between them has changed over the years and as she has matured," the insider added.

In 2012, Pattinson ended his relationship with the 28-year-old actress after it was confirmed that she had an affair with British director Rupert Sanders. Stewart and the father-of-two, who worked together on Snow White And The Huntsman, were photographed kissing in Hollywood Hills.

"She has been able to see her mistakes more clearly and feels bad about how everything ended. She misses what an amazing love they shared, especially when she hears about how happy he seems with Suki [Waterhouse]," the source went on. "It stings to hear that Rob may be deeply in love with another woman because, even though she has moved on too, Kristen still thinks about Rob all the time."

Meanwhile, Stewart had revealed she might consider dating men again. During an interview for Harper's Bazaar UK in 2017, she talked about her sexuality. She said: "Yeah, totally. Definitely... Some people aren't like that. Some people know that they like grilled cheese and they'll eat it every day for the rest of their lives. I want to try everything. If I have grilled cheese once I'm like, 'That was cool, what's next?'"

"I've been deeply in love with everyone I've dated. Did you think I was faking it? I've always really embraced a duality. And really, truly, believed in it and never felt confused or struggling. I just didn't like getting made fun of," she added.