Hey kiddo

Everything feels like absolute hell right now, but everything will eventually turn out OK. No hell, no matter how horrific, is permanent. Teenagehood passes, and eventually you'll be the master of your own destiny.
I know you feel incredibly confused: you hate the feminine shape of your body but don't really understand why; you find guys enormously attractive but you can't stand the way they focus on your curves; your so-called family is neglecting and abusing you. You think you're the only person in the entire world who's suffering in this way and you've learned to not talk about your problems. All of this is making it very difficult for you to study at school. But you know what? You're an incredibly smart kid, and you're going to (somehow!) graduate with A-grades and honours anyway. Because you're just that awesome.

When you get to 19 you're going to discover the reason why you feel so horrible about your body, but your research will tell you that surgical options are not good enough at the moment. That's fine; you don't need to rush into 'the surgery'. You'll think you're out of options and so you'll shove yourself back in the closet. That's a sensible idea in the short term, because you're right that transition is too big a burden when your mother is going through breast cancer. But sadly, she'll pop her clogs just a few years later and you'll be left with a young brother to care for. So put it on hold until then: move back to the UK as you planned, go to the doctor and get started on testosterone whilst you're still young & gorgeous and before your body gets wrecked by childbearing. Don't worry: your transition will be very successful and you can wait a couple of years for bottom surgery, by which time the techniques will have improved significantly. And you can still have kids in the meantime.
On that subject: whatever you do, don't marry that guy you fall in love with. He's adorable and wonderful when you first meet him, but that's only because he's putting on a front in an attempt to snag you. If you marry him he'll show his true colours whilst you're in a very vulnerable position and you'll spend the next 20 years in a difficult and often lonely marriage. He'll never get anywhere and he'll just drag you down. Plus he's a massive homophobe at heart, which will make your transition all the more difficult. Don't settle for that loser; you're worth a heck of a lot more.
The fact that you like guys doesn't mean that you're 'really a girl'. And you know how you feel when watching that gay character on
Hooperman? That weird mixture of despair, regret and deep longing? Put 2 + 2 together, smartypants: it adds up to 'you're gay'. It'll take time - and transition - for you to be able to fully embrace that fact, but when you do, oh my goodness! how your life will improve. Discarding the illusion of femaleness and living as your true self will be the greatest gift you ever give yourself. Enjoy it for as long as humanly possible.
Remember: no matter how dark & lonely things may seem,
I still love you. I'm enormously proud of my brave little soldier who managed to survive things nobody should ever have to experience. You made it possible for me to exist today, and I think of you fondly and with great compassion & gratitude.
And above all, thanks for being rubbish at committing suicide. Sticking around is definitely the best way to get back at people who try to drag you down.