Source: J.Lo is "Devastated" By Split

A lot of people were surprised when Jennifer Lopez and Marc Anthony announced their separation via a joint statement Friday, but a few of Jennifer's close friends tell Us Weekly that that the breakup was actually a long time coming.

Jennifer Lopez and Marc Anthony Split

Jennifer “tried everything she could to make it work," a source close to Lopez tells the magazine. "They went to marriage counseling. She was patient and loving and did everything he wanted her to...She exhausted all the possibilities."

Another source tells Us Weekly that Jennifer and Marc had a very rocky, very combative marriage. "They would get into heated, horrible fights. Then, they would also go through times where they were extremely loving and romantic...It was a roller coaster with them from the beginning." also spoke to a source close to Lopez and Anthony who revealed that the couple split "after months of nonstop arguing."

"Marc and Jennifer decided it's best to go their separate ways for the sake of their two kids," the source tells the website. 

A Timeline of Marc Anthony & Jennifer Lopez’s Love

Lopez's friends say that the American Idol judge will likely remain in Los Angeles with primary custody of her son and daughter. 

As for how she's handling the breakup, a source tells the magazine that "she is devastated...Absolutely beside herself. This is someone she dedicated a long time to, and that she truly loved. "

Still, a third source says J.Lo is looking forward to the future. "She is jumping back into work and being a mom with all her energy and she is really excited. She feels like she has grown leaps and bounds and is a new person now, better than ever!"

And speaking of moving on with her life, J.Lo was spotted on Sunday at MILK studios in Los Angeles where she had a photo shoot for a fall ad campaign for her Kohl's clothing line. A candid photo of Lopez shows her looking a bit somber in her first public appearance since she and Marc announced the split on Friday. Meanwhile, Marc, who performed in Colombia on Saturday, was in a much more playful mood, telling the audience: "They're saying I'm single."

EXCLUSIVE: Marc Anthony and Jennifer Lopez On What Their Marriage Was Like