People may have had faith that their siblings would look after them but i think a lot of the time it didnt work out that ay. If you could specify what era you mean we could delve a little further into that one.
With 'present moment pain' i hope i got the grasp of what you're saying. People fear the pain worsening which has an effect on the present pain, or have memories of a worse pain which they fear and also has an effect on present pain.
Both fears make the actual pain they feel worse. (Pain can be interchangable with suffering?)
In a social context - talking about past, present future, i just had a half hour chat with my sister about the near present, the past and the way distant past. I'd see this as a bonding thing that people do to relate to each other and is not a by-product of society but a part of what makes us humans in this world. OUr sense of the passage of time means we talk about past, present and future the same as we breath air. It's a natural trait.
As for 'living in the moment' - not what you said exactly but along the same lines - people worry about money because they have responsibilities that involve buying food, paying for their kids education, clothing, housing and such.
If people lived only in the present on a second by second term, i think our society would be very backwards. Spiritually more awake, but definately dark ages stuff. - I mean why invet something to make the work easier if you're only concerned with the present.
I hope i'm talking about the same kind of things as yourself?
What's important, to maintain a sense of self, is to reflect on your life ,and how you reacted to people, and they to you. A sense of worth and progress and usefulness.