Let me guess, you live in the desert SouthWest, or other warm southern states ? It's just a fact of life- widows abound in warm, dry locales. California, Utah, Arizona, and Nevada are literally crawling with them, and with the rate of reproduction they have ( by the hundreds ), they really can't be completely controlled. Just kill them as you see them. You do have one thing in your favor however, they are usually shy, and reluctant to bite, so unless you're hurting them or threatening their eggsacs, they generally try to avoid people, dropping to the ground or hiding in their retreats when disturbed. Also, they almost never leave their webs, unless they are destroyed. But I would still check my clothes, bedding, and shoes for them.