A University of California study showed that couples who use pronouns like "we," "our" and "us" showed less stress and were more positive toward each other. Those found to be less satisfied in their marriages used pronouns like "me," "I" and "you." Happy couples often speak in a "we." As in, "we had a nice time at the party" and "we had a major plumbing problem at the house last week." The idea is that unconsciously they've formed a sense of being a part of a team and life is happening to both of them.
Rather than waste energy blaming each other they see a problem as something they both need to solve. So they divide tasks, brainstorm, resolve and move forward. LIfe is better when the blame is minimized and the challenge (whatever it may be) is addressed by both people.
M. Gary Neuman writing in the Huffington Post