Love and Jealousy

Why jealousy always comes in your mind. Is that how you Love? Should be with our relationship has been running almost 3 years, you can better understand and know who I am. But the fact is you are increasingly not believe in me.
Yesterday you just made a fuss about a problem that I'm not important, and last night suddenly you are angry just because a friend sent me an sms asking news. How do I continue to trust you can give me? What else should I do?

I've been trying to contain his emotions and ego in me. I want to shout and say all feel in my heart. Not if you can feel how much I was afraid of losing you? How much I depend on with you? And it never occurred in my heart and mind, to far from you.

I want a relationship based in trust and mutual understanding. I learned to understand the attitude and yourself, so please help me understand more deeply.