1. Understand the self
You may see several people have come out criticising you, and while we normally do not allow flames in this forum, these comments have remained as they are relevant to helping you come to terms with this situation. Before you can criticize, judge, condemn, or even speak about others, you should have a good understanding of yourslef - how this information affects you, and how you want to deal with it. Your first reaction of disbelief and condemnation was understandable, as you were taken by suprise in a very unfortunate way. Your later rants about her cheating and being a fake...well, maybe you are just venting, giving yourself a way to deal with this. I suppose that is it, because this isn't to help anyone else, certainly not her, just for you to try and come to terms with this information and destruction of your 'first love' image.
2. Come to terms with the self and where to go next
Alright, so she wasn't who you thought she was, not even close. Only time wll really help you gain perspective on this, and even then the pain may never completely go away, it may become just a small dull ache when you think back on her. Getting even or doing things from spite will not help anyone, including yourself (other than a breif gloat, you'll still have the same hurt as before, with the added embarassment of not being a man about the situation, the embarassment of being childish and retailiating).
Perhaps later in life you'll understand this better. But for now, the best step is to stop any contact. Obviously anything to do with her just inflames your temper and hurts you more. Until such time as you can accept her and her decisions, the best thing for both parties is for you to not communicate with her. Tell her not to write/email/call until you contact her that you are okay with things, and that this may be the 12th of never, but the communication only hurts you more and lessens any chance of civil relations in the future. I have some thorns in my past, on a similar level, that I can't come to terms with - so I no longer acknowledge or communicate with that person. Any reflection on our past still causes that pain to resurface, but for the most part I leave it in the past and live my life with the lessons my experience with that person have taught me.
If, as I hope you will, you come to terms and accept this person with their choices then perhaps you can come to be a friend to them. I'm sure they could use a friend that truly cares, considering the tought life ahead of them. But to be a t4ue friend that cares, that means to give up your personal feelings of love, and just care for her as a person that is important to you. That also means accepting the fact that she does smoke (has smoked, may smoke again in the futur, whatever), has gotten pregnant at a very young age, and will probably be married at a very young age. you have to accept that that is who she is, who she has chosen to be. If you want those issues along with any good you see in her as the total package of a friend, great, start being a friend. If you can't, don't look back. Don't go back to clarify anything, to resolve anything, to hurt anyone or anything - it does no good. Just let it start falling into the past.
Either way, learn what you can from this. Let it help you decide what kind of person YOU want to be. What kind of a friend do you want to be, what kind of love and sex decision you wish to make from here forward witht the knowledge of how some decision can drastically change someone's life, and how it affects you directly and indirectly. Use this to learn and grow. If you can't be a friend to her, be a friend to the next person you meet who may be facing these choices, and give them the benefit of your experience. If you can be a friend to her, you may find more good or more bad...that's the risk we take with every friend, but at least with her, you now know where you stand.
