Kristen Marks Instagram
On Thursday evening, Kristen penned a heartfelt tribute to her late love, which she shared alongside a series of pictures from a beach photoshoot with the pair's two children: sons Beau, 2, and Mac, 4 months.
"What I would give to go back to this night," Kristen began the caption of her post. "At the beach, holding hands, kissing, laughing, throwing rocks, putting smiles on our babies faces. That's all we ever wanted to do. And we did it. And I will continue to do it."
"Today is one month without you. How??" she continued. "I could sit here and write about how this has been the hardest, worst month of my life, but what good would that do? Instead, today, I look back on this month and am in awe of how strong myself, the boys and our families have been."
"Our lives were turned upside down. Words can't even come close to expressing how much I miss and need you so I'm not even gona [sic] go there on here, but damn this sucks," added Kristen. "In the meantime keep sending me signs and giving me strength. We love you always, dadda 👼🏼."
On the evening of Aug. 22, Kristen and the late Boston Bruins star celebrated Beau's second birthday with Mac. Hours later, on Aug. 23, the father of two was pronounced dead by first responders at their Milton, Massachusetts, home. He was 31.
Jimmy's official cause of death remains unconfirmed. A spokesperson for the Massachusetts medical examiner's office previously said that an autopsy was completed, but the "cause and manner of death remain pending and an update is not expected for several weeks when toxicology testing comes back," read a statement obtained by PEOPLE.
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Shortly after her husband's death, Kristen shared a heartbreaking message on her Instagram Story, writing, "My angel I love you so much. I miss you. I don't know how I'm going to do life without you. You should be here. This isn't fair."
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Earlier this month, hundreds gathered at St. Ann's Church in Dorchester to pay their respects and say their final goodbyes to Jimmy at his funeral.
During the memorial service, Kristen was seen gently placing her hand on her late husband's casket before walking up to the podium. In her speech, she remembered him as a dedicated husband and father with a "heart of gold" and "infectious" smile.
"My dearest Jimmy, I cannot believe I am standing here a month after our three-year wedding anniversary," she said. "You were simply the best. There's no other way to put it."
Jimmy's younger brother Kevin Hayes, who plays for the NHL's Philadelphia Flyers, also delivered emotional words during the service. "He made me the best version of myself," Kevin said while fighting back tears.
Describing Jimmy as a "caring, loving, generous, loyal and determined" loved one, he added, "As a brother, he built us up every way he could. He brought joy and laughter into every interaction."