Relationship advice?

Hi ladies!! I need some advice...so my boyfriend and I have been together for a little over 2 years now and most of the time it's been really wonderful but he has a tendency to keep things from me if he assumes I'll react in a certain way. For example at the beginning I was super uncomf with the fact that he used weed a lot, so he told me he'd stop. At a year and 2 months he told me he'd been doing it the whole time. This has happened a couple times since then, with weed, alcohol, and then his ecig. It's not the stuff that he's using really that upsets me, it's the fact that he doesn't seem to respect me enough to tell me. We can't keep fighting like this and I really would like to stay with him...any advice?