Perry, 28, and Brand, 38, were married for 14 months, with their divorce over irreconcilable differences becoming final in February 2012.
"He's a very smart man, and I was in love with him when I married him," Perry told the Los Angeles Times. "Let's just say I haven't heard from him since he texted me saying he was divorcing me Dec. 31, 2011."
Perry said she had liked his humor until it got personal.
"Hysterical in some ways. Until he started making jokes about me and he didn't know I was in the audience, because I had come to surprise him at one of his shows," she said. "So. Hysterical to a point."
She said she takes responsibility for part of their difficulty in maintaining their relationship.
"I do admit that I was on the road a lot," she said. "Although I invited him time and time again, and I tried to come home as much as I possibly could.
"At first when I met him, he wanted an equal, and I think a lot of times strong men do want an equal, but then they get that equal and they're like, I can't handle the equalness.
"He didn't like the atmosphere of me being the boss on tour. So that was really hurtful, and it was very controlling, which was upsetting. I felt a lot of responsibility for it ending, but then I found out the real truth, which I can't necessarily disclose because I keep it locked in my safe for a rainy day."
Perry went on to date fellow singer John Mayer for a time.
"I still am madly in love with him," she said. "All I can say about that relationship is that he's got a beautiful mind. ... Beautiful mind, tortured soul. I do have to figure out why I am attracted to these broken birds."