They can use your help, too. Be emphatetic, and honest. Remember that any emotional support you give to the family member is a gift to the patient as well. Its better to make a specific offer. Offer to do errands for caregivers or to sit with the patient while the family does them.
Chores take energy.
Offer to take care of pets, flowers, shovel snow, mow the lawn, pick up a grocery list on your way to the supermarket. Food preparation takes time, and energy, and families in crisis don't have much left. Baked goods, homemade soups, and casseroles are especially helpful. Cards, letters, and personal visits to the family helps them that they are not forgotten. Transportation can become a major issue.