i didn't realise untill i was about 16/17 so pretty late but this was because for most of my life i tended to ignore myself. When i hit puberty it got harder to fit in so i was a bit of a social outcast but i still ignored myself, i just regressed further into my shell, my personality didn't have that much depth, i only made friends from similair hobies.
Honestly speaking i didn't act in away that was what i wanted, what i did was becuase i was trying to fit in, act like a what i thought a boy would be, act like i like this and that, etc; the worst thing is that i didn't realise i was doing this, it wasn't till i was 16/17 when my friend asked me what i wanted for my b-day.
We went around the shops and he said buy some jeans (never really war any) so i looked and wanted black ones, it was then i realised i didn't much like bright clothing, or tracksuits and i started changing my wardrobe, my interestes grew but despite the changes i was never really content, there was always somthing and i couldn't work out what it was.  I was happy that i was finnaly coming out of my sheld and discovering myself but i didn't like this fealing of not knowing somthing about myself so i searched despratly.

I don't remember exactly what cuased me to question my gender so it might not be 100% complete/right since my mind was such a jumble I'ts any wonder i remeber anything at all.

What caused me to change though, to really want to change was after i saw a video of myself, i saw it and i just couldn't help but feel disgust well up, i had really let myself go, i was ugly and really overwight(not obese but enough to be very noticable) so i decided i had to change, but that wasn't all iwas disgusted at but i couldn't work out what it was.
I rember at one point become completly obsessed with anime/manga/webcomics (anything really) that were gender benders, i don't remeber what peaked my interest in them  but somthing about it made me loose myself in it.
I think what happend was that it appealed to me becuase of my GID but i wasn't awear of it conciously at the time and somewhere along the line i think i questioned my gender. I looked into the mirror and i saw what it was that i could stand looking at, my masculinity, it was horrifying, this realisation and i wished i never realised it after i did.
I spent months agonising over whether i was transgender or not, going around in circles, over and over and over, afraid of what i would mean if i were. Eventually i realised i was never going to get my answer becuase i was asking myself the wrong question, I't's not "am i transgender?" but rather "am I what transgender means?" there is a big differance to that. It meant looking at myself, asking if i liked myself and why i didn't and in the end i got my answer, yes i am transgender becuase i am what it means, a person who hates there masculinty, physically and mentally, i grew horribly deprresed by this point, i still am.

I tried progressing from here but it's slow going, i'ts hamperd by my lack of confidence, i might seem condifent but i'ts not that, i just get on well with people. I'm rather shy about revealing things like this to people, but i'm a good judge of character. So far every one i've told has reacted as i predicted, in an accepting, trustworthy mannor, but i can't predict my father so i haven't told him yet.

Second question:
honestly i don't know, i haven't really thought about it, i guess it's pretty bad that we took so long to accept this but the fact that it has been accept means that were moving along, even if it's one step at a time. I don't know of this is an acceptable place for trans peple to live in but i guess it depends on where you live.
In london i'm rather weary of walking down the street even just presenting andro-male since most pople seam to take offence to my goth apearance, i'ts even more heart wrenching to do it in fully femm unless i'm with my friends. Up in derby though i'ts much safer, people seam to be more accepting, even if i don't have any really close friends up here i still feel safer.
I think we are improving but maybe not fast enough. There are three things i would change, the process with which one is to go through to change genders (i'ts like jumping through super pretentious hoops); make it less taboo by introducing the subject to young children where there most susptable to influence (both good and bad) and get them to understand it's not there fualt if they are trans and lastly take the condition out of the DMV since as far as i know, i'm not mental, i just have a birth defect.

@Atari: i don't understand your question