In the traditional sense, yes. My husband is my best friend, my life partner, and so much more.
However, a few years ago I redefined my own definition of soul mate. I used to believe in the traditional sense of the word -- that one person who is meant to be yours and yours alone, your predestined partner, or whatever you want to call them.
Now my definition of soul mate is drastically different. I believe that a person can have many soul mates, and that a soul mate is not just restricted to the romantic realm. To me, a soul mate is someone who lights you up in ways that others cannot, who just gets you, and understands you. It is someone that you connect with on a level that you just don't connect with other people (and I'm not talking sexually). At times, it can almost seem like you share a brain. In my opinion, a person can have several soul mates. In fact, I have two soul mates now (at least that I know of)-- my husband and a dear female friend-- and I'm sure I'll connect with more as the years roll by.