I'm a college writing teacher. In order to write this paper, you need to make the arguments yourself and present relevant support: you don't need to find sources that prove your thesis for you. I doubt very much that you're going to find anything in the medical literature that argues that "addiction isn't always an issue." If addiction were always an issue, doctors would not prescribe these meds at all. The fact is that addiction is a serious risk, and responsible doctors take that risk seriously. So they don't write journal articles about how addiction isn't a big deal, etc.
You can make your (own) argument effectively by citing addiction rates for various potentially addicting meds and arguing that statistics show that most people do not become addicted. You will need to do research about clinical findings on addiction rates. You can look at the Medline database for studies about that sort of thing. Your paper could also be enhanced with a couple of interviews of pain-management doctors, who should be able to tell you their experience in the field.
I think your paper should also discuss the difference between "addiction" and "dependence." A lot of people don't understand the difference, and I think that's the root of a lot of the suspicion that people have.
A good paper will also acknowledge the opposing viewpoint. I understand you're sick of it personally, but your paper will be better if you acknowledge that concern about addiction is in fact a legitimate concern. Argue from reason, not from emotion.
(And as an English teacher, I am duty-bound to point out that your sentence beginning "Being a college-level paper" contains a dangling modifier.

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Good luck with the paper!
Maisie