So I'm dating a married man

I'm 18 and im with a married man he's got no children only a wife we have been together 5 years he's 22 I visit him at work and he got his own office he shuts is blind and lockes the door and he chains me to the chair and we go at it 50 shade of grey style oh my Lord I'm so in love with this man it's sexy we have to sneak around and hide it from everyone I have even snuck in the house when his wife is a sleep and we have sex on the couch it's so fucking sexy but I feel like it's to much how do i tell him to end it with his wife and be with me

Just make it clear we wasn't having sex the whole 5 years it started when i was 16 I felt ready and he wanted to yes he married he got married when he was 16 we wasn't together then we was just friends 1 year in to his marriage we started dating