Boyfriend not listening

Update: yall I am leaving him 😭 I need to get some things set in place first. I’ve been relying on him and his car because I don’t have one atm I’m getting a car finding a roommate then leaving.

So my boyfriend has always had problems with his nose he had a heavy drug background and he said he was over it. I’ve had a lot of drug addictions in my life with my family members and them dying because of it. I told my boyfriend this and said if I found him doing anything other than smoking weed I would leave him. Recently he’s had more problems with his nose than ever and Im not proud of it but I went through his phone and found these. I talked to him about it and what I told him and he said he didn’t think it was a big deal but because it’s such a big deal (only after I found out) he’ll stop. I just don’t know what to do it feels like he doesn’t care and when I brought that I felt like that he said “how does it feel like I don’t care? I told you already that I would stop I can’t change the past” the texts were as earliest as less than 2 months ago. And he said he wasn’t hiding it but as you can see in one of the texts he says he has to hide it from me.