Hayden Panettiere Opens Up in Emotional First Interview About Her Brother’s Sudden Death: ‘I’ll Always Be Heartbroken’ (Exclusive)

Panettiere, 35, soon decided she didn’t want to leave the house, especially after being followed by pH๏τographers in the days after his death.

“I had to see horrific paparazzi pictures of myself coming out of Jansen’s funeral, which happened in a very private place, and it was shocking,” she says. “My agoraphobia came out, which is something I’ve struggled with in the past.”

Compounding her grief, Panettiere’s body physically reacted to the shock, and within days she became virtually unrecognizable. “I just ballooned out,” she says of the rapid weight gain she experienced.

She says the “stress and cortisol” going through her body resulted in the change, which diminished her self esteem. “I didn’t feel confident to put on clothes and get out of the house, but I also knew that I needed to get out and keep moving or I’d never stop looking and feeling this way,” she says.

Adding, “It became a destructive hamster wheel of, do I feel good enough to go out?”

She wanted to get back to work but had to find the courage to get out of her rut. When her publicist introduced her to personal trainer Marnie Alton last year, she says everything changed for the better.

Panettiere started slowly training with Alton, with whom she shared an immediate trust and connection. She especially loved the long walks they would take, where they’d just talk and Panettiere would share her stories from the past.

“These long, beautiful walks where we could vent and it would be this therapy session,” she says. “Marnie empowered me.” The endorphins Panettiere was getting from burning fat elevated her mood, too.

“My body just started reacting, not just from the working out. It allowed me to release the stress, the high expectations I’d always put on myself,” she says. As her insecurities faded, so did her agoraphobia. “There’s nothing like looking in the mirror and feeling like you look good enough to walk out the door,” she says.

She’s still learning how to live with loss but explains the new perspective she gained following Jansen’s death. “When something that mᴀssive has happened to you, you really learn to pick your fights and just not let the little things upset you,” she shares. “Because once something so horrific, so deep, so catastrophic happens in your life, there’s not much that can really rock you.”

Though she’s looking forward to the release of her new movie Amber Alert (in theaters Sept. 27) she’s mostly just grateful that she’s feeling more and more like herself every day. That doesn’t mean she’s healed from the trauma of Jansen’s death, or ever will be.

“I will always be heartbroken about it. I will never be able to get over it,” she says. “No matter how many years go by, I will never get over his loss.”