Life without her husband has been difficult for Lynda Carter.

In a new interview with People, the former “Wonder Woman” TV series star opens up about losing her husband, D.C. lawyer Robert A. Altman, in February, due to a rare blood cancer.

READ MORE: Lynda Carter Shares Heartbreaking Tribute To Late Husband Robert A. Altman: ‘I Will Love You Always And Forever’

Being on her own has meant learning a lot about herself, the actress reveals.

“The next part of my life is, I want to learn who I am,” Carter says. “It’s totally frightening. I don’t know who I am without Robert.”

The 70-year-old adds, “It still gets me. I just can’t believe I’ve lost him.”

Looking back on their 37-year marriage, Carter says, “It was a real romance. I was really trying to define love and loss and make sure it was about the human-ness of love.”

As Carter recalls, at the time she and Altman met, she was not actually looking for any kind of relationship.

“I was not prepared to meet anyone new,” she says, “I was going to do it on my own.”

READ MORE: Patty Jenkins And Lynda Carter Confirm ‘Wonder Woman 3’ Is Still In The Works: ‘We’re Super Excited’

Now, thinking back on their time together, Carter says, “We’d been through ups and downs and ins and outs, and I’d never in my life felt the love and the support and the thrill of having a guy like this.”

Among those ups and downs was Carter admitting in the ’90s that she had a problem with alcohol. Altman urged her to get help, and she has been sober ever since.

“Robert supported me through admitting that. The only thing he wanted was for me to be healthy and happy and okay.”