The actress, 27, played Kate Sharma in the second season of the hit Netflix show, which aired in April 2022.
Speaking to The Times, she said: "Therapy helps me clear my head. It can be a bit of a circus in this industry.
"There have been times when it was overwhelming, lonely and all a little bit crazy. The worst thing to do is to feel like the world is against you.
"Therapy has helped me learn how to communicate better, control my emotions and find useful skills for when things feel overwhelming. It means I can not take life so seriously and just enjoy it."
Ashley, who has previously starred in the Netflix series Sex Education, is set to appear in the upcoming film The Little Mermaid alongside Halle Bailey and Melissa McCarthy.
Last month, the star confirmed to Teen Vogue that she would be returning for season three of Bridgerton, which is due to air later this year.
In the Times interview, she also opened up about what it was like to film the show's famous sex scenes.
Ashley revealed: "We had champagne after we finished the sex scenes in Bridgerton. It felt like we’d done the hardest bit of the whole 11-month shoot.
"We did all of our intimacy scenes in one week. It’s a lot, gearing up for that every day and making sure you have enough sleep, doing whatever you have to do to make you feel ready."
The star also revealed that while her corsets on the show were "beautiful", she "hated" wearing them.
She explained: "Corsets push everything down to the bottom of your stomach. That means when you take them off, you’ve got a little bump.
"I hated wearing those corsets filming Bridgerton. They’re so beautiful, but I hate them – never again!"
Watch: Simone Ashley 'watched snails mate' to prepare for sex scenes