The singer, 44, said she struggled with motivation before she took part in Strictly Come Dancing in 2016.
She told the Mail On Sunday’s You magazine: “I did go out more than I’d ever gone out.
“I’d found a bit of a spark. I was enjoying myself. I guess I’d always been such a perfectly well-behaved pop star, and then I got married, had children and kept myself away from playing the game.
“But I remember reading headlines like, ‘Louise, out on the town, drunk again’ when I knew I’d been home at 9.30pm, sitting with my son having a bowl of Frosties.’
“Strictly switched a light back on.”
The former Eternal star split up with the former footballer in 2017 after 19 years of marriage and is now starring in the West End production of 9 To 5 and preparing to release her first solo single in almost 20 years.
She said: “Who gets a second chance, you know? I just didn’t think it would ever happen for me.
“I am pleased I did Strictly, because without it I think I wouldn’t have had the courage. Any woman who’s hit her 40s will understand that.
“But I don’t blame Jamie. I wish, three years ago, I’d been able to just speak up. For a long time it was easy to blame him.
“But actually, in the past six months, I’ve thought, you know what, it was down to me to say, ‘Something’s not right. My self-esteem is really struggling. I’ve got no passion. I love my kids more than anything in the world. I love what I do, too, and I haven’t quite got the guts to go out and try to do it again.’
“I just didn’t speak up. I don’t blame anyone else for that. I wish I’d just gone, ‘Right, the kids are getting older, and I love my job and I’m going to give it a real go, and Jamie, if you don’t like it, tough. But if you do like it, let’s talk about it’.”
Redknapp ruled out using dating app Tinder to find a new partner, saying: “No way am I ever going anywhere near that.
“Could you imagine? My two younger brothers are on Tinder and they have a horrific time!
“They get blown out, they don’t get replies. I don’t know, I haven’t crossed that bridge yet.
“I think if I met the right person, but... I think I have issues. I’m quite reserved. I’m not that person on the dancefloor, flirting with all the men. I’m more likely to go and sit in the corner.”