The 'Love Me Like You Do hitmaker - who married Caspar Jopling in August - admitted she used to be "much more irrational" and has had to learn to listen to other people's points of view.
She said: "I used to be much more irrational. I've had a lot of therapy and now I try to listen to people rather than talking all the time.
"I don't come across as an angry person, but it's definitely something I've had to work on for a long time."
The 32-year-old singer credits her husband for helping her become a more calm person.
She added: "When I met Caspar, this anger thing just went away. At first it didn't. I did that thing when you first meet someone you really like and you don't show any of your bad traits.
"I'd sit with my legs crossed and be really tidy and not swear. Now I've got a ring on it, I do whatever I want!
"But because he's such a calm person, he helped me see things in a different way. With Caspar I instantly felt calmer."
Ellie's father, Arthur, walked out on her family when she was just five years old and she believes her fractured upbringing contributed towards her feelings of rage.
Speaking on Fearne Cotton's 'Happy Place' podcast, she said: "I've had family stuff and I've had stuff in my personal life which probably made this anger get worse and worse. Therapy has helped me to get rid of things."
And the 'Starry Eyed' hitmaker has found boxing a useful outlet to getting rid of her anger.
She added: "Suppressing anger doesn't work. It is nothing to be ashamed of. Everyone gets angry, it's just about how you deal with it."