Draupadi given the gem

The Pandavas along with Krishna, Vyasa and Narada returned back to the camp. All realized that Bhima was alive because of Krishna.
Bhima gave the gem to Draupadi. She said I feel better. I want to say something. Please give the gem to Yudhistira. Let it shine on his crown.
Yudhistira accepted. He then asked Krishna How did Ashwatthama manage to enter our camp and kill the Pandavas in the night? Who blessed him?
Krishna said Shiva had protected the Pandavas for the eighteen days of the war. Ahswatthama came when Shiva was about to leave. he pleased Shiva and managed to do this. Shiva is innocent. As Rudra he destroyed the sacrifice of Daksha and then again as Vyomkesh, he blessed Daksha. All Gods have done what they could by worshiping Shiva.
Krishna said Leave all grief aside. Get ready to take over the kingdom. Rule well.

Yudhistira took the blessings of Krishna and said he would follow his advice. 

Bhima goes after Ashwatthama

Yudhistira kept grieving - What is the use of the kingdom when I have lost my dear ones.

Bhima said this is destiny and there is no point crying. If you are there, you can regain everything back. This is a cycle of life and death. You do not know where you will be next. So do not grieve. The ones who have passed on have just left the body, their soul is there. You are a learned person. You should not grieve thus.

Draupadi said I will be consoled if you get me the head of Ashwatthama. On his head is a gem. I want that gem. Then I will be relieved. Else I will kill my self and die with my sons and brothers. You are the one who killed Kichaka and Hidimb and Jatasura. You can do this. You drank the blood of Dushshasana and broke the thighs of Duryodhana. As a brahmana, Ashwatthama has behaved like a rakshasa.

Bhima asked Yudhistira for permission. Yudhistira said this was fair. Bhima decided to leave with Nakula as his charioteer. Seeing this, Krishna said - Yudhistira, do not send Bhima to get Ashwatthama. He is a great archer and Bhima will die if he comes face to face with the son of Drona. Only a great archer can defeat him. Let me tell you something.  When you were in the forest, once Ashwatthama came to me in Dwaraka. He said he had the knowledge of the Brahmashira weapon and wanted to exchange that with my discus. I gave him my discus and he could not lift it. He said that the brahmashira weapon that was capable of destroying the world, and left. Yudhistira, for someone who has the knowledge of such a powerful weapon, you need to think and then decide.

Yudhistira said What do you say then? What should I do? Bhima has already left.

Krishna said Then let us follow him.
Saying this, Krishna along with Arjuna left to catch Aswatthama. Yudhistira followed them.

Ashwatthama seeing Bhima, took a blade of grass, and reciting a mantra hurled that towards Bhima. The grass became a ferocious weapon. Blazing, it sped towards Bhima. Seeing this, Krishna asked Arjuna to use a weapon taught by Drona to counter this weapon. Arjuna released the weapon.  The earth started shaking and it seemed that all would get destroyed.

Suddenly Narada and Vyasa came there and stood in the middle of the weapons. They said the earth would end if they did not withdraw their weapons. Arjuna, with the help of mantras withdrew his weapon. Arjuna did so. Ashwatthama said he had released the grass in anger and did not know how to withdraw it. The weapon once released had to kill. It would kill the unborn child of Abhimanyu and return back.

Arjuna said he wanted to cut off the head of Ashwatthama. Vyasa asked Ashwatthama to give the gem, he had on his head, to Arjuna. Vyasa said When you take the gem out, a wound will form. That will never heal. For years, you will roam the earth in pain.

Ashwatthama gave the gem to Arjuna. Vyasa said I will try to relieve you a bit. On earth, if people take your name three times and drop some oil, that oil will soothe some of your pain. The ones who take your name three times before applying oil on their bodies, will be relieved of their sins. Aswatthama then left.

When the weapon entered the womb of Uttara, Krishna entered the womb and revived the unborn child. 

Yudhistira's and Draupadi's grief

Janmajeya asked - What happened when the Pandavas realized what had happened?
The sage said -
The charioteer of Dhristadyumna had managed to escape somehow. With the sun rising, he decided to inform the Pandavas about this.
He found Yudhistira and said The army of the Pandavas has been killed in the night. Dhristadyumna, the sons of Draupadi and many brave warriors have been killed by Ashwatthama who entered our camp in the middle of the night. All were sleeping and never realized what struck them. All are dead except me. I somehow was left for dead. Having managed to escape, I have come here to inform you.

Yudhistira was angry. He said - What Gods assisted him? How did he manage to do this? The brave warriors would have been sleeping tired from battle and they were killed thus. The sons of Draupadi were jewels of our eyes and they were mercilessly killed.

He then sat down on the ground and said - What I wanted and what have I finally got? All is lost. I was happy with the sages in the forest. I have not recovered from the shock of losing Abhimanyu and I am hearing this now.

Draupadi fainted when she heard this. Shrieking loudly, she started crying out for her sons and her brothers. She said I have been through hardships all my life. When Arjuna won me, I lived in the forests and worked like a maid. And what do I get in return? I was insulted in front of all and my clothes were snatched off me. I was insulted by Kichaka and was saved by Bhima.