Robert Pattinson and FKA Twigs' engagement news quickly made headlines during April 1, leaving some fans to believe the exciting news was a cruel April Fools' joke on Robsten fans, however, now that the news has been confirmed, some are wondering: what does Pattinson's ex-girlfriend and "Twilight" costar Kristen Stewart think of the news?

Inquisitr reports that according to sources close to the actress, Stewart is "heartbroken", adding that she's in disbelief that Pattinson would tie the knot so quickly with Twigs after only five months of dating while she and the actor dated for several years.

A source reveals, "When Kristen first heard that Rob and FKA Twigs were engaged, she felt devastated. She doesn't want to believe it's true and was seriously hoping that this was just some sort of April Fools' joke."

The source continues, "After only five months of dating, she can't believe Rob would propose to FKA. She and Rob dated for years! Hearing this has really taken a blow to Kristen's confidence. She was holding out major hope that there wasn't any truth to their engagement."

To make the situation more saddening, the source also dishes that at one time, Stewart held out hope that Pattinson would propose to her.

"Kristen is especially hurt to hear that Rob is engaged to FKA because marriage is something she obviously spoke about with Rob when they were dating. Of course they did, they were together for so long! There was a point where she definitely wanted to marry Rob and she would hate to see him do that with another girl. She knows it's her fault she never got to marry Rob, but still hearing that he's engaged still really stings."

While Stewart publicly apologized after her cheating scandal in which she was caught having a relationship with her married "Snow White and the Huntsman" director Rupert Sanders, she and Pattinson eventually split months later.

While Stewart has kept a low-profile since splitting from her "Twilight" beau and is taking time to focus on her career, there's no doubt that the "Still Alice" actress is taken aback by the sudden engagement news from her ex.

This article orginally appeared on fashionnstyle.com