Is porn a form of cheating?

Andrea • Hi my name is Andrea I`m 21 years old have a 1 and half year old baby boy I`m a full time student and work full time
My boyfriend of 6 months watches it without me knowing like hiding it and I think it's disrespectful and gross and in my previous relationship my ex husband watched it and i didnt tbink anything of it and ended up cheating on me bad! (With all my best friends) we are both 21 years old not if age matters but what do you lady's think is it considered cheating?