In a discussion of this gravity, it's probably better to define your terms. "Happiness" is not easily defined within one individual's psyche, let alone across cultures, etc.
I have used some sort of recreational psychoactive chemical for more days of my life than not, be it a double espresso or a cigarette or three speedballs a day.
I don't particularly subscribe to the idea that drug users have some sort of "void" in their souls that they are trying, in vain, to "fill" with drugs.
Drugs make a person feel a certain way, without fail (pretty much). If you desire "Feeling/Emotion Z", take "Drug Z," and that feeling is, for all practical purposes, guaranteed. Very little in life is so simple.
Am I happy? Pretty much, these days. It depends on too many factors to begin to chronicle now.
It is very important to make the distinction between happiness and sensual pleasure (especially
emotional sensual pleasure), contentment, etc.
Have I always been happy Absolutely not. The old cliche is true: You have to experience Hell to appreciate Heaven, or even Purgatory, for that matter. A lot of proactive soul-searching, and variety of experiences is essential, too, IMO.
Live your life, observe others' lives and their reactions to consequences. If you're paying the slightest bit of attention, something like happiness is bound to befall you, eventually.
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