Britney Spears' ex-husband, Kevin Federline, is speaking his mind in the wake of Spears' revelations in her new documentary.

In an exclusive interview with People magazine, Federline is recalling his life of bliss with Spears and their tumultuous divorce. The rapper and dancer is pictured on the cover of the latest issue of the magazine with his and Spears' sons, Sean Preston, 3, and Jayden James, 2.

Federline told People that getting married to Spears was a a "really, really, happy, exciting moment." He told the magazine that he and the singer were working on the making the marriage work out of concern for the children, and he was caught off-guard by the divorce.

"I mean, we were having complications," Federline told People. "I didn't give her an ultimatum, but I was trying to work stuff out with her, and she didn't even talk to me or anything and went behind my back and filed (for divorce). (I was) completely blindsided."

Federline addressed the child custody issue, and the assumption by people that it was only for the money.

"My first question to (my lawyer) was, "Am I ever going to be able to see my children?" I told him that I would spend every last dime that I had to make sure that my children are OK ," Federline said. "That's all that mattered. I didn't know how much power Britney had. That really scared me."

Spears filed for divorce from Federline in 2006. The couple's divorce became official in July 2007 after nearly three years of marriage. Their custody battle of their two sons ended in July.

Federline won custody of the children earlier this year. He receives $20,000 per month in child support payments from Spears, according to settlement documents.