Soul Mates

I have read a quote from you stating that people come into our lives for a reason and for our own evolution.  I totally believe this to be true. I have been married for 12 years and recently met someone else that I fell in love with.  I did not have an affair with this person because I felt it was important to see what feelings I had in my current relationship especially since I have two small children.  I have been trying to discern if the purpose of the other person coming into my life is for me to reconnect with my spouse or to be with this other person later.

I am grieving the loss of the relationship with the other person since I ended our friendship/relationship.  I have shared with a couple of friends and a clergy member about this other relationship and they all seem to want to dispel my belief that soul mates exist.  I am feeling the pain of the loss of the relationship but I feel I am also grieving the loss of my belief that soul mates exist.
My question is do soul mates exist and how can I discern the purpose of this person coming into my life?