Jealous? Who, Me?

Apparently (to the shock and surprise of absolutely NO ONE), I'm a bit of a jealous person. No, not in a Fatal Attraction kind of way, mind you, but definitely in a lose-my-marbles with worry type of way. Did someone cheat on me at a younger age? No, not that I can recall. In fact, the worst thing I can remember happening was snooping in my boyfriend's car when I was in high school and finding a note instructing him on how to break up with me. Nice. I definitely learned NOT to snoop anymore, lest I find out something terrible again. I wish I knew how to be calm, cool, and collected and realize that I'm worth being with and stop second guessing everything. When does one reach that state of coolness? Because I'm ready to enter that phase just about....now.