Michelle Trachtenberg's boyfriend Jay Cohen has broken his silence following her death

Jay wrote on his Instagram page, which is private: "I am so grateful to all of you are in my life sharing our common joys, helping me with tragedies and healing from pain and grief.

"I'm sure many of you know what I mean when I write that."

Jay told a user who commented on the post that he would share more about the star "one day soon".

He added: "Michelle was loved by so many."

Michelle portrayed the troublesome Georgina Sparks in Gossip Girl and her untimely passing was met with an outpouring of grief from the show's cast.

Leighton Meester - who played the character of Blair Waldorf in the show that aired from 2007 until 2012 - described her co-star's death as "devastating".

The 39-year-old actress told Flaunt magazine: "It's devastating.

"She was a wonderful, talented person, and everyone loved her.

"It's very, very sad for everyone who knew her."

Leighton explained that Michelle's passing made her realise how powerful Gossip Girl's legacy is.

She added: "Now, I can see that [the show's legacy] continues - in some ways, even more so than back then - to live on, which is incredible."

Fellow cast member Penn Badgley explained that he found news of Michelle's death "surreal".

He told E! News: "I can't claim to have known her well but it's surreal. Really surreal, really saddening.

"What I remember of her is she was incredibly quick to laugh. She was really joyous. We all have our ups and downs, our lights and shadows, but she had this - I mean, she was mature, but she had this childlike, joyous laugh."

Meanwhile Taylor Momsen - who starred as Jenny Humphrey - said that the tragic news had left her "heart on the floor".

She wrote on Instagram: "In shock... When I met this girl 17 years ago I knew we'd be friends.. she was smart and sassy, bold and sensitive, funny as f*** and filled with fire. She was simply awesome.

"I'll miss our late night calls that no one should ever hear but us. She was always in my corner and there to support me whether I was right or wrong.

"I will miss you everyday my love.. I think we truly understood each other and I am so grateful to have had a friend like you in my life for so long.. (sic)"