Hold her/him. What Giok said. Be there, even if they say they don't need you. When it hits them, the enormity of the loss, be there with hugs, a quiet touch, a drive in the country, a look through old photos, etc, when they are ready. Don't be afraid to leave them alone, though. Do not try to push through the grief or make it seems as though they should be "over it" any time, soon. Society used to honour a whole year of mourning...it can take time and support of any kind is appreciated, usually. A quiet word, etc. would not be amiss.