caught watching porn

when would you say its the time that porn is getting in the way of your relationship.. me and my fiance have been together for almost 7 years and the last fee months hes just been soo off and i couldnt figure it out until tonight i had caught him in the action. and he still wanted to lie about it but on top that iv just noticed thibgs havnt been right he hasnt been himself he hasnt been how he usualy is to me latley. hes been off sneaky and not wanting anything to do with me no wanting sex kiss nothing at all... i just dont known whats going on cause he wont tell me... and he knows how dealy it hurts me so badly about watching porn i try to let it go but inside it kills me