Shut-Up Insecurities and Let Me Be

I am in a wonderful relationship, the kind where you see the person and light up because your heart starts pounding even after so much time has past and you think they can't surprise you anymore. Where when you are feeling down they know what to say and it is so sincere it makes you want to cry for different reasons, because you feel so loved. Where when people ask you about that person you can't convey how wonderful they are or why they make you so happy, but you know inside why they are yours. You fit together, surpassing physical connectedness, an indescribable relationship.
I feel as if secrets are revolving around my relationship...is this because so many others are messed up I wonder why I am so lucky? That it must not be real? I know that I am slow to warm, but will I always be on edge? The mind is a strange device, get hurt once and you carry it with you forever. I know that if I keep being paranoid, not trusting in the one I love, I will create opportunity for heartache. I already find avenues to be upset, making myself miserable because my mind goes straight for the worst.
Women are raised to think that sex is an act for the one person you will spend eternity with, sacred, serving a purpose of procreating with your soul-mate. Men are raised to believe that their lives have not been lived unless they have physical relations with more than one person. Society feeds into these thoughts, separating men and women and yet we continue to pass on these "standards" to our children.....when will we think for ourselves? Do we even know what our own thoughts are anymore? There are women who worry that their loves will leave if they aren't giving enough, so three-somes occur, porn, a variety of sexual acts. And then there are those who hope that even though they don't do those things, they will still be loved, that there are not secret, late night phone calls, indecent website photos called "art" to make one feel justified.
Relationships are hard, I guess the key is to stop trying to fit into the mold you think everyone wants you to be in, be yourself and find the one that supports you.