Boyfriend Smoking Weed

Hello everyone, I was pretty indecisive about coming on here and spilling the beans since I am a somewhat casual private person..

but I’ve gotten into a situation which I don’t know how to handle... any advice welcomed!

So, me and my boyfriend have been together for three years. He was never really a drinker or smoker at all, he really didn’t have a thing for it and neither am I, I have yet to even try any of those things. Mind you, we’re 19.

He has had a good paying job for a year now as a salesman and couple months ago leased an apartment. I saw that he started buying THC oil cartridges and at first he would say it was for his roommate, but then I would see them all the time in his vehicle so I was upfront and asked and he says that he does smoke out of a pen every now and then since everyone at his job does it too that’s where he got the idea from. I was like OK, cool, as long as it doesn’t lead you into bad habits. But 1 cartridge started turning into like 5 cartridges by his nightstand and vehicle and it kinda threw me off..

Couple weeks ago I started noticing the smell of weed (skunk smell) in his apartment and again, I was upfront and asked and he admitted to me that he smokes weed now because it’s a “stress reliever” from work.

Which I get, but I don’t see how it is helping much and here’s why.

1. He has a short temper now, small things throw him off

2. He’s not very clean anymore, and leaves his place/vehicle messy and doesn’t really take care of hygiene now

3. When he’s driving, he drives recklessly now and fast which he never has ever (basically the asshole on the highway)

4. He’s never been the smoker/drinker, and tbh it’s a turn off for me if a guy does those things

5. I strongly do believe weed can become a gateway drug

I don’t want to be controlling and say stop because I am not his parent and at the end of the day it’s his life choice. But I have to admit it is bothering me just a tad.

What should I do?