The Take That star confessed earlier this year to cheating on Emma Ferguson multiple times but says they have overcome their "very difficult" time and want to stay together forever.
Mark - who has children Elwood, four, and 23-month-old Willow with Emma - said: "I do want us to grow old together. I do fancy her. The feelings are there."
The 38-year-old star also hopes that fans don`t assume `What Do You Want From Me` - a track on Take That`s forthcoming album `Progress` - is about his marriagedifficulties as the song was penned long before their public troubles.
He said: "Even now a part of me is thinking, `Maybe it doesn`t have to be on there.`
"It`s a song that`s always going to be related to a time in my life that was very difficult.
"It`s obvious why people can make the connection with lines like, `It`s been a difficult year. I like to think of us moving on. I still think I`m in love with you, still want to make love to you."
Instead, Mark claims it was written as a positive song about a couple`s future together and he forces himself to focus on the origins of the song when he listens back to it.
He explained to Britain`s Q magazine: "The song was written as an optimistic song and then when everything came out it took on a different connotation. I have to keep reminding myself that."
`Progress` - the first Take That album to feature Robbie Williams since 2005`s `Nobody Else` - is released next month.