The drug life is an ugly life, Thea. You have lost the innocence of youth, simply by being within range of its destructiveness. There is no love in that world. God, Goodness, and Light are not to be found in the darkness that is the drug world.
Just as young soldiers who return from war need time and help to heal from the shattering of their innocence, you need the same.
Whoever loves you in your present life, parents or other relatives, longtime friends or teachers, whoever loves you, reach out to them and let them know you need them. Tell them what has happened to you, and let them know you need their love. More than ever.
You did nothing wrong, loving that young man, but truly, the power of evil in his life will not be influenced by love. Not yours, not anyone's. Drugs destroy human connection. You did not know. You know now. So you must walk away and never have contact with him again.