The Oklahoma City bombing thrust Diane Koch into the life of a crime victim's advocate for 13 years, until she realized she had to leave the state to start a new chapter of life.

Bud Welch said his ability to eventually forgive enabled him to survive emotionally after the death of his daughter. For Jannie Coverdale, though, there's "no such thing" as moving on, even after two decades.

All three lost loved ones 20 years ago Sunday, when Timothy McVeigh blew up the Oklahoma City federal building with a rental truck laden with explosives. However, all three took different paths as they tried to come to grips with a pain that never fully heals.

Koch initially sought justice for her husband and the 167 other people killed in the attack, eventually becoming an advocate for victims of all crimes in a role at the Oklahoma attorney general's office.

"It was my life for 13 years," Koch said. "I just had a heart for those who have been hurt by crime — and still do."

But the intensity she threw at her job prevented her from letting go of the trauma of April 19, 1995.

"The first few years, I couldn't see beauty anywhere," she said. "You can't even see sunshine. You're blinded to anything positive, it seems like."

McVeigh and Terry Nichols were convicted of conspiring to detonate a truck filled with more than two tons of ammonium nitrate and fuel oil outside the Oklahoma City federal building and of the deaths of eight federal law enforcement officers, including Koch's husband, Secret Service agent Don Leonard.

McVeigh was eventually executed and Nichols will spend the rest of his life in prison.

For Koch, now 68, remarried and living in another state, moving on meant moving away.

"Peace was such a hard thing to access for so many years. It's a wonderful thing to access now," she said. "You can let go of it being the controlling thing in your life every day. There is life beyond April 19th, not that April 19th goes away. It's still a part of each and every one of us. But you can focus on other things and have a wonderful life."

Welch's slain daughter, Julie Marie Welch, was a 23-year-old Spanish-language translator for the Social Security Administration. He said his emotional journey has allowed him to become a resource for the families of other victims of terrorism, including relatives of victims of the Sept. 11, 2001, attacks.

"I think me traveling and speaking has helped me a lot with my healing process," said Welch, 75. "I've had many of them come up to me and say: 'How do I get where you are?' I say, 'I've had more time than you have.' It takes time to go through a process. It takes a lot longer for some than others."

Initially filled with rage over the murder of his daughter, Welch said he forgave McVeigh and Nichols in 2000.

"When you're able to finally forgive, it releases you. It has nothing to do with the perpetrator of the crime. It has to do with you," said Welch, who has become an outspoken critic of the death penalty.

"Killing someone else is not part of the healing process," Welch said.

Donna Weaver, whose slain husband, Michael D. Weaver, was an attorney for the U.S. Department of Housing and Urban Development, said she has managed to have "fun memories" again after raising two sons who were 16 and 12 when their father died. Each anniversary is tough, though.

"April is not my best month. There's a cloud, a weight that descends on me," she said.

Jannie Coverdale, whose 5-year-old grandson Aaron and 2-year-old grandson Elijah were killed, said time hasn't really healed her pain.

"I miss my boys," said Coverdale, 77. "There's no such thing as going on with your life, not the life I had before the bombing. I'm still trying to build a new life. And I don't know if I'm ever going to get it accomplished. Too many memories."