The singer, who released her new album Two Eleven this week, credited the late Whitney Houston with helping her believe in herself again.
"There were times when I tried to come back and it didn't work. Then I started to feel like, maybe this is not my purpose, maybe this is not what I'm supposed to do, because it's not happening to me," Brandy told CNN.
"People are calling me a has-been, people are calling me washed-up and all these things. That starts to affect you mentally a little bit because you're like, 'Am I? Do I still have it?'
"Clearly there was another plan in place, and I was able to connect with that destiny plan that is within us all and make a different choice, to believe in myself so I can do what I got to do to have a relationship with the people that love my music."
Brandy also revealed that the title of her new album - Two Eleven - is a tribute to Houston, who passed away on February 11 - Brandy's birthday.
"To lose my idol who introduced purpose to me, a dream to me, on that day - it solidifies our bond and what I need to do to go forward. The time is now," she explained.
"I will never get over Whitney passing. I just have to do what I promised her, and I have to follow the words she gave me right before she died - which is another strange thing, that we talked right before she passed on.
"I'm in a great place and I feel like she's with me. I feel like she's helping the angels and God to guide me to do what I have to do."