Jealousy isn't something that people set out to experience. Nor is it easy to control once it gains a foothold. I had an ex who was extremely jealous of me, to the point where I had to leave him. He couldn't understand that I was not likely to cheat on him. I was very shy and it just wasn't my style. But that didn't stop him from accusing me whenever I took an innocent trip to the library or the bakery. He would ask me where I was going, then show up there later to spy on me. Yet I have experienced the pangs of jealousy (not about the ex, mind you) and no, there is no logic to it and it is very hard to control once it gets started. 
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Dreams are renewable. No matter what our age or condition, there are still untapped possibilities within us and new beauty waiting to be born.
-- Dr. Dale Turner