The Irish singer - who has been blamed for the group not yet reconvening from their two-year hiatus - insists she doesn`t worry about the fact she has grown apart from Cheryl Cole, Kimberley Walsh, Sarah Harding and Nicola Roberts.
When questioned about which band member she is closest to, Nadine said: "At the minute, none of them. We`ve known each other since we were 16 and everybody moves on. It`s like when you go on holiday with someone and say, `Let`s be friends forever!` It doesn`t work out like that. It`s just one of those things."
Although the girls are no longer friends, Los Angeles-based Nadine insists she bears no personal grudge and claimed she had enough friends of her own without having to rely on her former bandmates.
She told Fabulous magazine: "I don`t speak to the girls, not regularly. But that doesn`t mean there`s a problem on my part - there are loads of people that I don`t speak to regularly.
"Me and the girls always work together really well. But don`t worry because as far as friendships go, I`ve got loads and loads of friends. I`m really not struggling in that area."
Nadine also revealed she had tried to make contact with Cheryl but had not received a reply to her message.
She explained: "I texted her when she had her single out, and I bought the album, but no, I haven`t heard from her in quite some time. It`s probably because she`s busy and doing whatever."