If you dream that you are in art gallery it means that you will be disappointed, when facing the truth. You are someone, who is having problems when trying to pretend as being a happy person, when you are not the one. It is hard for you to be someone you are not when you want completely different things.
Dream dictionary: Art Gallery dream meanings
To visit an art gallery, portends unfortunate unions in domestic circles. You will struggle to put forth an appearance of happiness, but will secretly care for other associations.