This is just my take on it but I do realise that there are far wiser people who know a lot more about the subject than I do, I use to think that there are basically 3 groups but I am wondering if that should not be 4 groups .
Group 1, The man who just likes to wear a skirt and has no thought of being feminine at all .
Group 2, The cross dresser who likes to dress to feel feminine for the length of time while they are dressed.
Group 3 , The transgender who feels like they have both genders within them regardless of what they are wearing .
Group 4, The transsexual who knows that they were born in the wrong body .

Now just to complicate things if you are at the higher end of your group then you can jump up to the next group with 3 being the biggest contender for this to happen.

As for intolerance I beleave that I am a mix of all groups in other words I have been or am any one of those groups at a given time so I would like to think that I am tolerant and understanding of all types of dressing .