Sometimes you click and sometimes you don't!
Isn't it funny how sometimes you meet someone - say, at a party, in the grocery store, on an airplane - and you feel like you've known them forever?! And yet there are others that you have known forever where that spark just isn’t there.
Recognizing this phenomenon has kick started the process of detachment that many thought leaders advocate - focus on relationships where your growth and evolution will come from and worry less about definitions that have been created by simply being a family member. Definitions like mother, father, brother, sister, etc. Your "family" is where you feel most at home and sometimes that comes from complete strangers.
Strangers - yes perhaps in this life. I would argue those that you feel an instant attraction to may have shown up in your life before (albeit not this one!) Personally I experienced this notion when I first got married and met my now niece - related to me by marriage. I felt a soul connection with her from the first day we met. A connection that transcends this life. While I have no idea what we were to each other in a previous life, I am convinced she was an integral part of my journey. We even get asked all the time about whether we are related! And the next life? Well maybe we will take on different roles the next time around but something tells me that we will mean something significant to each other.
So go where your heart wants you to go - get lost in the beauty of feeling so connected to someone that you don't even need to talk to understand/ be understood. Respect all that come into your life, regardless of the relationship definition. Resist the temptation to be bound by the structures of the family tree. And when souls depart from your life rejoice in the fact that you were blessed with their presence - for 5 minutes, days or years.
One day engrossed with the right person can gift you years of learning, growth, and enlightenment. You'll know when you click right away - that this interaction has the hand of The Divine in it.