Rachel Riley and her husband have reportedly split after 16 months of marriage.
The 'Countdown' presenter's partner Jamie Gilbert is said to be "devastated beyond belief" by their separation, which is believed to have come out of nowhere.
A friend of Jamie's told The Sun newspaper: "He has no idea where this has come from. Rachel just told him they had grown apart."
A source confirmed to the paper: "They are separated. Rachel is away filming much of the time. Jamie's stuff is still at the house so he hasn't technically moved out.
"The whole family is very upset. They adore Rachel and everyone believed she and Jamie would start a family.
"They obviously fell in love before she was famous and for whatever reason, she now doesn't feel they have a future together."
The couple met at Oxford University and tied the knot in August last year. They originally broke up in 2009 after four years, but got back together when Jamie proposed on Rachel's 25th birthday in January 2011.
The news comes one month after Rachel was voted off 'Strictly Come Dancing' in week six, where she was partnered with Russian professional dancer Pasha Kovalev.
The brainy beauty's profile has sky-rocketed since she took over from Carol Vorderman on 'Countdown'. She also co-hosts 'The Gadget Show' on Channel 5.
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