I'm talking all varieties of relationships; lovers, family members, co-workers, friends... etc, they all have the same purpose.
To activate whatever longs to be transformed within you.
That's it. Whether it's that relative that triggers you every time you see them, sometimes without even saying a word, or that friend or lover who's company feels so good. It's all for the same purpose. The trigger is just as valuable as the soothing sensation of being around someone who doesn't activate any negative feelings or discomfort within you.