"How can I help my husband to stop picking fights with family and friends?"
It's possible that your husband enjoys the conflict. In her book on addiction and the ADD mind, When Too Much Isn't Enough, Wendy Richardson writes, "The energy produced by the conflict is painful, but it's also activating."
Find a calm time, and tell your husband how you feel when he picks on you—and what you see when he picks on others. Ask him what he gets out of this behavior, or what he expects to happen.