Why is transsexuality a bad thing?

The answer is pretty simple.

And God created man to his own image: to the image of God he created him: male and female he created them.  (Genesis 1:27)

He created them male and female; and blessed them: and called their name Adam, in the day when they were created.  (Genesis 5:2)

It's pretty clear; God created men to be men, and women to be women.  That's the end of it.

And before you accuse me of hate, I don't hate anyone.  I'm simply stating a truth.