About ready to walk away

So a little background first. I was engaged to a man whom I had a child with for 5 yrs, our son is six. He was abusive then and an alcoholic and the things he put me through physically and emotionally scarred me completely. I learned then that I would NEVER put up with addiction again. After I left him he took custody of our son (primary because I worked all the time and he had no job so they viewed that as better somehow). Ever since then Im protective. I see our son and we coparent well as he has changed and we do whats best for our son. Fast forward 5 years, I am married to another man and im currently 22 weeks with my second son (his first). He has always been a sweet man and been there for me when I need him. I mean I married him lol I have an issue though. He does pills. Hes always done one here or there and its never been an issue until now. For the past 4 or 5 months now its becoming an everyday thing. He claims his back hurts or some shit and goes and spends 140 bucks on some hydrocodone every two weeks. Everytime he gets them he has lied to me about it until i finally told him off and said that he needed to tell me the truth. Now its only half truths and he promised me a week ago that he would stop doing them for a while and now here we are a week later and he got 20 more today. Hes so damn high its ridiculous and i didnt even know he got 20 until 10 mins ago. With me going thru this shit before I told him if it was gonna keep being a problem im leaving. i refuse to raise a child in this. Am i wrong?