When I read your post two things ran through my mind: Barbara has found purpose through giving and a life with purpose is one of life's values. It gives you reason to get up in the morning, and it affirms a sense of self at a time when that sense of self has been so shattered. I think feeling whole, even if lonely, is so much better than that awful experience of "going to pieces."
You say you could only cope in those first months, but think again. When we met only days/weeks after our husbands left us, we were giving to one another right from the first moment. We were giving in understanding and companionship just as surely as we were taking from one another. To be sure, this took a different form than Barbara's...who is somehow "on call" to strangers.
But it bears out what you wrote in Fresh Widows: "Mother said, "Never talk to strangers." I loved Mom, but she was wrong on this....I think I'll tell my children, "Let a stranger in your (life) and your misery will disappear."