The success of “The Girls from Ames,” the best-selling book about the 40-year friendship of a group of women originally from Iowa, has prompted a spate of national news stories about the importance of friendship to emotional and physical well-being. One study shows that if you have lots of friends you’re likely to live longer, while another concludes that friends help slow memory loss (boy, do we hope that’s true!).

Another, not-so-healthy friendship finding: If your friends gain weight, you probably will, too. For good or for ill, all the studies say, friends make a big difference in our lives, maybe even more than family.

We’ve been thinking a lot about friendship lately. Cokie recently joined her Wellesley classmates for their 45th college reunion. There, she reunited with a group of women who have always stayed in touch and have been getting together quasi-regularly for the past 20 years or so.

Unfortunately, a sad occasion quickly overshadowed that happy one – the memorial service for another college friend of ours, Eden Ross Lipson. Hundreds of people canceled their summer-weekend plans last Saturday to honor Eden’s life.