where do I turn for help?

Thank you in advance if you actually read it and offer an opinion, I'll answer any of yours as thoughtfully as I can.

I've been going through a fairly dark downward spiral recently. I was introduced to drugs, which is slightly the problem but not nearly all of it. It mainly stems from a girl, imagine that. I told her that I didn't believe in love, based on my childhood and how f*cked up it was growing up. She didn't understand my side and well that was basically the end of us. Recently I have fallen hard for her, and told her how I felt, laid it all out on the line. She rejected me, now I'm pretending like I don't have feelings anymore and she is coming to me for advice about guys. I love her to death and want to be her friend if nothing else. But with this whole situation and doing coke, and m, and anything I can get my hands on, I'm afraid my life is going downhill. I have a great job, but no one I trust enough to say this to. If anyone I would actually talk to said girl, but that wouldn't really solve anything I don't think.

I can't tell my family about my drugs, but they would understand better the girl situation. I don't have any close friends that would understand the girl situation but they may be less judgmental about the drugs. It's just hard to not have someone for all of it, because it does link together. Should I see a therapist? It just seems like they won't understand any of it, I need advice not just someone to say these words to. Where do I turn?

(Don't mention religion please)