"We haven't decided where, and as soon as we make that decision it will happen very quickly," Sheridan, 44, tells the U.K.'s Mail on Sunday's YOU magazine.
What Sheridan does know with certainty is that she wants to start a family. "I would like a baby," she says, though she is reluctant to say if the couple are trying.
The two, engaged since March 2006, have been vacationing over Christmas on the Caribbean island of St. Bart's.
Of Bolton, 54, she says: "Michael is a wonderful human being. He has brought me a profound love and support. He is an amazing sounding board for me. … I am the happiest now I've ever been in my life, feeling more grounded than I ever have."
She adds, "For me there's only been one person, and that's Michael."
Scrabble ConnectionHaving first dated for about a year and a half starting in 1993, Sheridan and Bolton reconnected in 2005 and matters grew serious – though during those years apart, they still kept in touch, thanks to a certain word game.
"We have always been an inspiration for one another and had this deep love," she says, "even when we were apart as friends. We had an ongoing Scrabble tournament by e-mail for close on two decades. I won the last five games in a row."
They also collaborated musically, with Sheridan singing vocals on Bolton's "The Second Time Around," despite her fear of singing.
"My mother [actress Sally Adams] has an extraordinary singing voice. She said I couldn't sing, so I chose to believe that," Sheridan says solemnly. "It was Michael who lured me out of my shell. He cured me. It was such a big achievement."