Maria Sharapova said she fought for the truth so she can end her career on her terms.
The former world number one was initially banned for two years after failing a doping test before having it reduced to 15 months on appeal to the Court of Arbitration for Sport.
Sharapova will return to action at the Porsche Grand Prix in Stuttgart, playing her first match the day after her suspension runs out on April 26.
The Russian's impending return has been the hottest topic of conversation in tennis, with a number of players expressing discontent at Sharapova being given wild cards into the biggest tournaments on the WTA Tour.
Sharapova herself appears to see no reason to show remorse.
Speaking at the ANA Inspiring Women in Sports conference in California, reported by The Desert Sun newspaper, Sharapova said: "You always want to end your career or a chapter in your life on your terms and in your voice, and to be in a moment where you felt like it could have ended on someone else's terms was very difficult to accept. And that's why I fought so hard for the truth to be out.
"You don't realise how much you love something and how much something means to you until you lose it for some time."
Sharapova has spent her time away from tennis focusing on her business career.
The creator of Sugarpova sweets took classes at Harvard Business School and spent time shadowing NBA commissioner Adam Silver, at Nike headquarters and as an intern at an advertising agency.
The 29-year-old also wrote her autobiography, which is due to be published in September.
Sharapova said: "I learned that life is okay without tennis, which is a very scary thought because once you've done something for so long you think, 'What am I going to do when I don't have that?'
"But my mind and my body still have the motivation to be the best tennis player I can be. I got my day job back."