Please read before jumping to conclusions.
New neighbours moved in to the flat below us; we have the upstairs flat, they have the downstairs (I think it was a big house divided up). They're nice but they smoke indoors and the smoke is coming up through and making our flat reek. I cannot stand the smell of cigarettes or tobacco, it makes me nauseous. DH says that there's nothing that we can do and to be honest, I'm not even sure what I'm BU about. AIBU I guess to think that this isn't on? DH doesn't want me to speak to them about it but I literally cannot live like this.