"Not that anyone should care, but in order to not give the press the chance to invent crazy and hurtfull drama, I prefer to tell my fans personally that Nick and I have decided to be apart," she wrote on her WhoSay page.
"We have being having too many problems with figuring out how to spend time together and becouse of my work and now his, its been getting worse and worse, not fun anymore," Vergara wrote.
"We are still very close but we belive is the best thing for us right now."
The breakup announcement comes after nearly two years of engagement and two years of dating before that.
Loeb, a businessman, proposed to Vergara at Chichen Itza during a July 2012 Mexico trip celebrating her 40th birthday. Of course, two months before the proposal, the couple were rumored to have broken up, allegedly because of the Colombian actress' rising fame.
No big wedding had been planned, as it wouldn't have been a first marriage for either of them, Vergara told Cosmopolitan in June 2103.
"When he proposed, it was my birthday, and I'd flown more than 100 family and friends to Mexico for six days of partying. It took me forever to arrange the logistics!" she told the magazine. "If I had known I was going to get engaged, I don't do this stupid birthday."
In addition to her work on "Modern Family," Vergara has endorsement deals with Diet Pepsi, CoverGirl and many more companies.