Jacy Nittolo/Instagram Ray Liotta and Jacy Nittolo
In a heartbreaking Instagram post Thursday, Nittolo shared a series of photos featuring the couple smiling and posing together and with their family.
"It's hard to believe a month has gone by," she began her caption. "There are no words to properly describe what one goes through with this type of unexpected loss."
The actor, best known for his roles in Goodfellas and Field of Dreams, died in his sleep on May 26 in the Dominican Republic, PEOPLE confirmed. A source told PEOPLE no foul play is suspected in his death and that Nittolo was with him when he passed.
"I miss him every second of every day," Nittolo wrote in her post.
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Jacy Nittolo/Instagram Ray Liotta (R) and family
In her post, Nittolo also included a photo of the couple with who she referred to as "our children": Dax, Chazz, Jade, Joey and Liotta's 23-year-old daughter Karsen, who is his only child with ex-wife Michelle Grace.
"Each day my hint of some light is being with our children-Dax, Karsen, Chazz,Jade & Joey," Nittolo wrote. "Through such deep pain I find so much love and laughter."
While she went on to say their "lives right now are so fragile," Nittolo added that the family is "holding each other up" amid their grief.
"It's as if we are one big blended family that was predestined beyond our wildest imaginations," she concluded.
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Nittolo previously released a statement on Instagram two days after Liotta's death, paying tribute to her late fiancé alongside a series of shots of the pair from over the years.
"My life these past couple of years have been nothing but truly magical. Ray and I share a deep love that I will cherish in my heart forever," she wrote in the caption. "We laughed daily and we were inseparable. The chemistry was wild in the best way."
Then writing that Liotta "was everything in the world to me," Nittolo continued, "We couldn't get enough of each other. The kind of real love that one dreams of."
She concluded, "He was the most beautiful person inside and out that I've ever known … and even that is an understatement."