Brad Pitt is hitting a low, probably the nadir in his life, as he battles for the custody of his children.

After spending 12 years with Angelina Jolie, and backing her in every way, he is just not prepared to let the past go. He does not want to get involved in any new relationship, nor let his love die out.

"Brad has no desire to date or get involved in any new relationships," a source tells HollywoodLife.com "He is still stunned and heartbroken over his failed marriage, and feels like it'll be a long time before he's ready to love again."

Hence, Brad feels crushed that his custody battle with his estranged wife Angelina Jolie over their six children - Maddox, 15, Pax, 12, Zahara, 11, Shiloh, 10, and eight-year-old twins Knox and Vivienne has still not been resolved.

Pitt does have good friends like George Clooney, who have been egging him to move on in life and meet new friends. However, Pitt hasn't been too social.  While his friends like Clooney have been urging Brad to get out, be social, and meet beautiful women, Brad Pitt has turned only to his work, not his social life.

Recently, Pitt has been working with French beauty Marion Cotillard on 'Allied', in which there was one steamy scene shot in the back of the car. which shows him sharing a hot time with her. But that was only a shot. Even though he was paired with a number of heroines - Jennifer Aniston, Marion Cottilard - Pitt hasn't really wanted to get another life. He is still too attached to his recent past.

Currently, a new girlfriend is really the last thing on his mind: "His main focus right now is finishing up his work obligations and figuring out how and when he can see his children," says the source. His children are still his priority. While the actor-turned-producer was cleared of child abuse allegations, his permit for joint custody of the children is still not completely clear.

A source told Us Weekly magazine:  "He's crushed. He wants to limit the fighting. Brad has been deferential on what's best for them and limits their stress. You don't just immediately create a new world."