Q: How can I comfort a family member who has recently lost her husband?
A: In the writings of the Lubavitcher Rebbe we consistently find that one must believe and meditate on the fact that the soul of the departed is always with his or her beloved, and participates in all the events of their lives. It is also important to remember that soon, with G-d's help, with the Resurrection of the Dead, they will be reunited.
One should do as many good deeds as possible in the merit of the soul of the deceased, and recognize that the will of the deceased is that his/her beloved should be in a state of happiness, brought about by the performance of mitzvot. The joy of fulfilling a mitzvah is the most effective type of joy.