Hz. Julaybib was from Ansar; he was a bachelor. The Prophet wanted to marry him off. He asked somebody from Ansar to marry his daughter. That person said, "I will ask her mother about it." He went to his wife and said that the Messenger of Allah wanted their daughter to marry. The woman thought the Messenger of Allah wanted their daughter for himself and said, "Yes." When she later found out that he wanted her for Julaybib, she said, "No." When her daughter heard this, she said, "Are you rejecting the Messenger of Allah? Marry me off to Julaybib. The Messenger of Allah never wants a bad thing for me." Thus, the girl showed her commitment to the Messenger of Allah. Thereupon, the Companion went to the Prophet and said he would marry their daughter off to Julaybib. After the preparations were made, the wedding was held.
Only a short time after the wedding, the Prophet started to prepare for a battle. Julaybib was newly married but he did not want to miss jihad. Hz. Julaybib accepted the call of the Messenger of Allah immediately. He fought heroically in this battle. Finally, he was martyred. When the battle was over, the Prophet said, "Where is Julaybib? I cannot see him. Look for him." The Companions looked for him. They found him near seven polytheists. Hz. Julaybib had killed them and then he was martyred. They informed the Prophet about it. The Prophet went there. He said, "This person lying here is from me and I am from him." He repeated this sentence three times. Then he buried him with his own hands.
Hz. Julaybib’s wife was waiting for her husband. When she found out that he was martyred, she thanked Allah Almighty for being "the wife of a martyr". When she heard the following prayer of the Messenger of Allah for her, she became very happy: "O Allah! Send goodness to her abundantly! Do not make her face any hardships throughout her life." Because of this prayer, everybody envied her; they helped her a lot. 
Musnad, 4: 421; Usdul-Ghaba, 1: 292.