I spoke with many teens when I used to teach bible class at Frayser Mission Church in Memphis, TN. The two biggest concerns most teens have when deciding to make God a permanent part of their lives is, "If there is a God, why is their so much pain in the world" and "With everything fun going on, it's too hard to be a Christian." At that time, I never knew how to approach these responses. But I am going to approach them now.
I believe that pain equals growth. Without pain there will be no growth. We won't be able to excel as a people without trials in our life. The fact that there is pain and we can make it through is a perfect example of God's existence. Romans 5 :3-5(KJV) says, "And not only so, but we glory in tribulations also; knowing that tribulation worketh patience; and patience, experience; and experience, hope: and hope maketh not ashamed; because the love of God is shed abroad in our hearts by the Holy Ghost which is given unto us." So to all those teens who has lived through tribulation in their lives or seen others go through pain and tribulation in their lives, embrace it! Take it and use it to grow closer to God, not further away. Use that pain, to learn about yourselves and the people around you. You won't become the person you are destined to become without it.
It's true, as a Christian you are sometimes ostracized and you feel left out of many things. But the only reason you feel the way you do is because you truly have not come to the understanding of the awesome sacrifice that was made for your benefit. If someone you knew sacrificed their child because of their unconditional love for you, wouldn't you do what they wanted you to do? Even if it makes you feel odd? Just think, God just wants what is best for you and your life. He wants the best for you and everyone around you. No matter what you have been through or done, He is willing to adopt you as His child and love you with a love so great no one you know can match it. He wants to heal your heart when it's broken and carry you through your struggles. He wants to give you eternal life in paradise. I think that is worth feeling left out or strange and weird. "But in all things approving ourselves as the ministers of God, in much patience, in afflictions, in necessities, in distresses, In stripes, in imprisonments, in tumults, in labours, in watchings, in fastings; By pureness, by knowledge, by long suffering, by kindness, by the Holy Ghost, by love unfeigned, By the word of truth, by the power of God, by the armour of righteousness on the right hand and on the left, By honour and dishonour, by evil report and good report: as deceivers, and yet true; As unknown, and yet well known; as dying, and, behold, we live; as chastened, and not killed; As sorrowful, yet alway rejoicing; as poor, yet making many rich; as having nothing, and yet possessing all things. "(2nd Corinthians 6:4-10 KJV)