Is it because we don't care what strangers think of us or because we do?
Is it because our friends and family will accept whatever treatment we dish out and not abandon us?
Do we take advice and information from strangers more seriously that we do friends and family?
It’s because were used to them. Over the years, we learn to tolerate our friends and family. Many of the things they do that used to annoy us, we get used to. We also trust them. As such, we feel comfortable enough to talk and act openly with them (no holds barred). We speak our minds (politics, workday problems, etc.), we exchange secrets (we ‘know’ each other), we don’t always wear our “Sunday best” in their presence (holey jeans and t-shirt), and so forth. We act natural (and expect them to do the same).
When we’re around strangers, however, that level of trust isn’t there so we revert to “polite mode”. That facade we put on do others won’t see us as we really are.
With family members, we feel like we can “let our guard down”. They won’t chastise or ridicule us even when we make foolish mistakes. They’re always there to “watch our backs” so to speak. That’s something we dare not do with strangers. However, once strangers become friends, we begin to let our guard down with them as well. Yet, it anyone – family member or friend – breaks that trust, w have a hard time letting it go (we may forgive, but we don’t forget). If the breach of trust is too big (unrepeatable), we abandon them. We dump the friend, we divorce the spouse, we stop talking to the family member, etc.
Humans are social animals. Whether we think so or not, we long to trust others. We’re born that way; it’s in our nature. Notice how trusting young children are. It’s when they learn that not everyone out there can be trusted that they become wary. Even so, we still want to trust others. If we didn’t, we’d never want friends and we wouldn’t care about family. We want that stranger to be a friend. So were polite to them and, hopefully, they to us. Of course, we also earn that there are just some people who cannot be trusted. We tend not to be as polite to those individuals.