John Stamosis struggling to cope with the death of his dear friendBob Saget.

On Thursday, Stamos, 58, opened up about his grief onTwitter, sharing: “The mornings are hard. Middle of day comes in waves. Mostly bad. Nighttime is hard.”

“I miss getting a text from him right now. Me answering. Him saying he’s too tired to respond. Me saying, ‘Then why’d you text me so early?'” he added to which Saget’s widow Kelly Rizzo responded,writing: “I feel this John. ALL day is impossible. And I feel this part too. Bob would text me a question and I’d respond right away and he’d say “I’m busy I can’t talk” and I’d say… ‘hey! You texted ME!’ "

Stamos alsosharedon Friday, “Today will be the hardest day of my life. God, grant me the serenity to accept the things I cannot change, courage to change the things I can, and wisdom to know the difference.”

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Saget died unexpectedly on Sunday at the Ritz-Carlton hotel in Orlando at age 65. He had performed a stand-up set earlier Saturday night and was found dead in his hotel room the following afternoon. There were “no signs of foul play or drug use,” according to theOrange County Sheriff’s Office.

Stamos, who worked with Saget onFull Housefrom 1987 through 1995,first spoke outjust hours after news of Saget’s death broke, writing: “I am broken.”

Bob Saget and John Stamos at the 2006 Cool Comedy, Hot Cuisine fundraiser for the Scleroderma Research Foundation.John Shearer/WireImage

Bob Saget; John Stamos

Stamos also honored the late comedian with aheartbreaking tributeon Instagram.

He added, “He’s standing on stage, killing! Another two-hour set in front of a couple hundred of the luckiest people on the planet. They’re laughing so hard, they weep.”

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John Stamos and Bob Saget.Chelsea Lauren/Getty

Actors John Stamos (L) and Bob Saget

Stamos continued, “On his way to the hotel, he calls his beautiful, loving wife, Kelly. He says he feels 26 again, alive! Then asks her to fix up a picture he wants to post. She tells him it doesn’t need fixing, and tells him how handsome he is. He tells her he loves her with every bit of his heart.”

“And when he gets to the hotel to put his head on the pillow, he misses his daughters, his family, his friends. God, he loves us all so much,” Stamos wrote. “And he goes to sleep dreaming of when we’ll all meet again — and he’s smiling. I know in my heart he’s smiling, still hearing the laughter from a few hours before.”

RELATED VIDEO: Celebrating Bob Saget’s Beloved Character Danny Tanner: “It’s Very Nice to Make People So Happy”

Saget and Stamos famously played brothers-in-law, Danny Tanner and Jesse Katsopolis, who move in with their college best friend, Joey Gladstone (Dave Coulier), to help raise Danny’s three daughters — D.J. (Candace Cameron Bure), Stephanie (Jodie Sweetin) and Michelle (Mary-KateandAshley Olsen) — after the death of Danny’s wife. The show also starredLori Loughlin,Andrea BarberandScott Weinger.

They continued, “He was a brother to us guys, a father to us girls and a friend to all of us. Bob, we love you dearly. We ask in Bob’s honor, hug the people you love. No one gave better hugs than Bob.”

source: people.com