One friend said: "Chris wanted to spend all his free time with Jen - there was a discrepancy between how they viewed their relationship, she's so easy going and he's quite intense."
And she also told friends that the Coldplay frontman, 37, was so keen on their being together that he wanted to spend all his free time with her.
But throughout the brief relationship, Martin remained close to his estranged wife Paltrow, with whom he has two children, daughter Apple, ten, and Moses, eight - another source of strain for the pair.
He and Paltrow, 42, announced in March that they were 'consciously uncoupling' after ten years of marriage.
The source told MailOnline: "Jennifer said Chris is an all or nothing kind of guy, so she chose nothing. She broke up with him late last week.
"He was completely blindsided, he was really sad about it.
"Jen is contractually obliged for the next six weeks to promote Mockingjay and she just couldn't see how it was going to work."
The couple were first publicly linked in August, shortly after Jennifer split from her long-term boyfriend, British actor Nicholas Hoult, but are believed to have first struck up a romance as early as June.
They quickly became a hot item and were spotted enjoying an intimate afternoon for two at the Wolffer Estate Vineyard just a few days before Jennifer's birthday on August 15.
A source told E! News at the time: "They were there on a date. They were very low-key, nobody realised who they were. The setting was super-romantic."
The pair were seen sampling wines together, with the source adding: "They watched the sun go down together, then quietly left."
They then shared a string of quiet date nights at Martin's Malibu home and the romance seemed to move further into the spotlight on September 19, when Lawrence attended Coldplay's performance at the iHeartRadio music festival in Las Vegas.
Jennifer Larence at the iHeartRadio concert with Chris Martin in the background. Photo / Getty Images
But throughout everything, Chris stayed close to his ex-wife Gwyneth.
The ex-couple were even pictured enjoying an intimate sushi dinner in LA last week with Oscar winner Gwyneth tenderly stroking Chris's face as she left.
The singer met up with Jennifer later that night.
And another source claimed to MailOnline: "Jen got tired of watching Chris play happy families with Gwyn and was annoyed that he was trying to keep her hidden away."
But a source close to Martin told US Weekly that their relationship had been "rocky" due to their "insane" schedules, adding: "They really like each other, but it's just so complicated with so much going on."
And while Lawrence is believed to have had a crush on Martin since she was a teenager, another source told US that the British singer was equally enamored and believed she was "the real deal".
Hours after the split was confirmed, a rather downcast looking Jen was seen going to dinner with her dad Gary in LA.
A source confirmed to People magazine that it was indeed Jennifer who did the dumping, saying: "Jen is the one who broke it off with Chris."
Mockingjay, the first part of the final two movies from the Hunger Games series, is released on November 21 by Lionsgate.
Representatives for both Jennifer and Chris declined to comment.
- Daily Mail
