Is it wrong I feel this way??

So my boyfriend used to addicted to meth pretty bad...but he's got clean...he's been clean for almost 2 years...So my boyfriends mom does meth. Well he went to go stay a few days with her. Well I'm okay with him spending time with his mom but I rather him not spend days with her cause of her drug problem... And I'm scared that she might talk him into doing it again. I trust him...but I don't trust his mom(&step dad)

So am I over reacting, or do you think I have a reason to think this??