You sound like you need someone in your life to guide you in your spiritual path. In the Orthodox tradition we're encouraged to find a spiritual father; someone with great faith, wisdom, and spiritual maturity who we can go to for help rather than trying to struggle alone. Pray to God and seek out someone like this in your life.
Try your best to avoid temptation. Sex outside of marriage always complicates things and may lead to heartbreak or worse. Remain pure, if your bf really loves you, then he'll marry you. If he doesn't, then he wont. Simple as that.
Love God and put Him above everything, this is the greatest commandment. Follow this and your path will be straight. Continue in your study of Christianity and pray to God from your heart and He will hear you.
I hope this helps. You're in my prayers.