What you're in love with are the memories and feelings of your time with him when you were young, carefree and in love for the very first time.
The reality of it is, you are now an adult, married with children. Perhaps you feel a little bored in your current situation and meeting him again gave you a little excitment and rekindled that young and in love feeling.
This guy tells you he is going through a divorce, but people have a habit of telling you what they think you want to hear, when they want something. For all you know, he could be "happily" married, but looking to have a sexual fling for a time.
My advice would be to stay strong, concentrate on your family, look to your future and stop living in the past. You are no longer a 14 year old kid and there are other people's lives at stake too, namely your husband, kids and the family of the guy you once knew. Sever all contact with this person.