Yeah, it gets better as women age but I think it's more due to estrogen levels than anything. Younger women are in their childbearing years so it might be a competition thing among women in that age range. Older women...finished bearing children, can sit back and relax so no need to compete for male attention. Estrogen levels decrease as women get older...it can bring on a sense of peace and tranquility...post-menopausal, that is. Women in the throws of menopause...well, we can only hope that all involved with them make it out alive! Been there, done that, ain't trying to go there again. So older women who are past their childbearing years can focus attention on being friends with other women as opposed to younger women who might look at each other as a threat to their territory.
Just an idea that's not based on research as opposed to personal experience...
Queenie