To pray is to pay attention to something or someone other than oneself. Whenever we so concentrate our attention that we completely forget our own ego and desires, we are praying.
Ideally, friendships lead us into deeper communion with each other; those we love mirror the divine reality and so draw us closer to the One they reflect. In our humanness, however, we can forget that the friend is only a reflection of God and instead invest ultimate meaning in the relationship.