I'm sorry for your pain and glad you found us.
Maybe he needs to avoid the people and places where he used drugs? That's not uncommon, or maybe he is again lost in his addiction and you have no place in his life.
No matter what the reason, it might be good to take time and look at what draws you to such a relationship, where you are doing all the giving and he is doing whatever he wants and using drugs.
I hope you find a better way to live without him, life doesn't have to be this sad and complicated at your young age.
And please accept this with understanding that I say it because I care...don't ever presume you are not "the addict type". Sweetie, it happens to the best of people, rich and poor, old and young, and often those who think it will never happen to them. Addiction happens to those who use drugs.
Hugs