How do you explain transsexualism to non transsexual people?

I have started slowly coming out to close friends and family. But as I do they keep asking me the same themed questions asked over and over again.

"How do you know you are a transsexual?"
"Whats makes you think you are a transsexual?"
"What do you think you can do as a women that you can't do as a man?"
"I just don't understand."
"You are too masculine you will never pass as a woman so why try?"

I know I am a woman on the inside, and I try to tell them it is about me making my outside match my inside. But that is not clearing it up for then they are still confused. I believe they mean no disrespect, they just want to understand. So they keep asking the same themed questions over and over. I feel I must not be explaining it clear enough.

Is this typical for people who are coming out? Or are my friends and family being to nosy? Does anybody have a good simple answer to help me explain what I am going through to non transsexual people?

Would you be upset if you found out that your neighbor was a transsexual?

What would you do if you found out that your neighbor was a transsexual?
1. Would you stop speaking to your transsexual neighbor?
2. Would you tell the rest of the neighbor hood?
3. Would you be afraid to let your children play outside?
4. Would you stop letting your children play with your transsexual neighbor’s children?
5. Would you try to get the neighbor hood association to bring legal action against your transsexual neighbor?
6. Would you accuse your transsexual neighbor of bring down the neighbor’s property value?
7. Would you vandalize your transsexual neighbor’s property?
8. Would you tell your transsexual neighbor, they are breaking Gods law at she is going straight to hell for all eternity?

What would you do ???

Now consider what would you do if you’re the transsexual?

Would you leave your spouse if they were diagnosed with gender dsyphoria?

If your husband or wife told you that the consular they had been seeing had diagnosed them with gender dsyphoria. (Meaning they were a transsexual but had not start to transition.) Would you stay with them or would you leave? Which ever you would do please explain why?