Being Rational

Where does Jealousy come from? And how do you deal with it? I woke up this morning with feelings of hurt and anger. We had some friends over for dinner last night and they of course share their stories of how they met. I am sure they don't have a perfect life and they have their trials but as I listened the jealousy and anger creep in. I know rationally that it isn't their fault and that where I am in my life is just one moment and that I will work through this. But it seems like once I start feeling optimistic and that I will have a full life, something reminds me of what I lost. Maybe I need that reminder so I don't become complacent again and so I keep growing but it still hurts. It makes me think of how much I loved Joseph and how much I miss him. Who he used to be anyways. How do you feel that emptiness? I know I am not ready for another relationship and I know everyone keeps telling me that I will find someone else. But I don't believe it, I want that feeling of being together but feel like it wouldn't be the same. I have three boys that I love and cherish which will make things so different then the first years of marriage. And I am afraid I would never be able trust anyone else again.