LEOMINSTER (CBS) —  One day after the breakthrough in the murder of Vanessa Marcotte, her family says they are still processing that an arrest has been made.

Marcotte’s cousin, Caroline Tocci was close in age to Marcotte, had grown up alongside her in Leominster.

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“It doesn’t get better, it just changes, I’d say. Grief is a complicated process,” Tocci told WBZ-TV on Sunday.

Vanessa Marcotte, 27, was found slain near her parent’s home on August 8, 2016. She had been out for a jog while home from New York and visiting her parents in Princeton.

State Police arrested 31-year-old Angelo Colon-Ortiz in Marcotte’s murder on Saturday.

Tocci called Marcotte’s death the “most shocking thing that’s happened in [her] life.”

“She was my other half, she is my person, and it is hard to believe,” Tocci continued.

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An arrest does not bring back Vanessa, said Tocci, but it is a “relief.”

“It’s the first step of justice for Vanessa.”

Focusing their efforts on the Vanessa T Marcotte Foundation is also helping Tocci and her family cope. The organization is dedicated to helping women live free from violence.

Tocci explained, “I think the only way we can move on from this is if we can help others in this situation and feel gratified from that work. And that’s exactly what Vanessa would do.”

Another cousin, Steve Vittorioso, described the extended wait for an arrest.

“It was a long eight months for everybody involved,” he explained. “And that’s where we as a family just really leaned on each other and just being in close contact with Vanessa’s friends too. We all just came together and really rallied behind each other.”

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On June 17, the Vanessa T. Marcotte Foundation will hold a 5K Walk and Run at Wachusett Mountain. That date would have been Marcotte’s 28th birthday.