"The split has been tough," added another People source. "You go into a marriage thinking it's going to be forever. When you realize it's not, it's really hard -- especially when a child is involved."
Frankel and Hoppy met in November 2008 and got engaged 11 months later. They wed in March 2010 when Frankel was seven months pregnant with their two-year-old daughter Bryn. The couple separated due to ongoing issues in their marriage they couldn't resolve with time or effort, Us Weekly reported late last month.
While Hoppy has been spotted recently wearing his wedding ring still, Frankel has apparently been looking "frail and drained," according toIn Touch Weekly.
An eyewitness who saw Frankel dining with two friends at a restaurant in Aspen, CO, on Christmas Eve -- just one day after she had announced her marriage of almost three years was ending -- told In Touch, "I didn't see Bethenny eat anything... She looked really skinny."
"She was quiet and seemed sad. She looked tired and much thinner than on TV," added an insider who saw the reality TV star shopping that same day.
On December 25, another witness reportedly saw Frankel at a sushi restaurant and was also taken aback by her petite body frame.
"She was very, very thin," said the witness.
"It was devastating for Bethenny to be without Bryn for Christmas," a source close to Frankel told In Touch. "But this was something Jason wanted, so she agreed. She always wants to do what's best for Bryn, even if that means that she has to be alone."
The Bethenny Ever After series showed footage of Hoppy and Frankel -- who first appeared on reality TV when she competed on The Apprentice: Martha Stewart in 2005 -- struggling in their marriage, and reports had circulated for months that the couple was on the verge of calling it quits.