Simpson

WENN

Jessica Simpson is said to be feeling "insecure" after discovering that ex-boyfriend Tony Romo is in a new relationship.

Romo, who dumped Simpson, 29, in July, is reportedly romantically linked to 22-year-old beauty queen Candice Crawford, sister of Gossip Girl's Chace.

"[Simpson] can't believe it. She doesn't want Tony back, but no-one wants to see that their ex has moved on with a hot, younger girl," a source told Hollyscoop.

"This couldn't have come at a worse time for Jessica. It's opened up a lot of old wounds. She's pretty insecure about herself."

The insider added: "Jessica is unlucky in love and that's her downfall. She's buried herself in work and trying not to focus on the break-up with Tony."

Recent speculation has suggested that Simpson is back together with John Mayer.