The Leeds-born vocalist, real name Melanie Brown, has said she turned to alcohol to "numb the pain" of revisiting memories from her marriage to former husband Stephen Belafonte for her upcoming book.
Brown, 43, told The Sun on Sunday newspaper: "The past six months have been incredibly difficult for me."
"Sometimes it is too hard to cope with all the emotions I feel. But the problem has never been about sex or alcohol - it is underneath all that.
"I am fully aware I have been at a crisis point. No-one knows myself better than I do - but I am dealing with it.
"I have made the decision to go into a proper therapy programme in the next few weeks, but it has to be in the UK because I am very, very British and I know that will work best for me."
A judge in Los Angeles ordered Brown to pay 350,000 dollars (£270,000) of her ex-husband's legal fees and she must also pay him 5,000 dollars (£3,800) a month in child support for their six-year-old daughter Madison.
Ms Brown said a PTSD diagnosis was helping her to address her issues.
She said: "I am still struggling but if I can shine a light on the issue of pain, PTSD and the things men and women do to mask it, I will do.
"I am speaking about this because this is a huge issue for so many people."
Ms Brown added: "I'm not perfect, and I have never pretended to be.
"But I am working on being a better version of myself for my kids - whom I love more than life itself - and for all the people who have supported me."