Any advice welcome

I have a huge decision to make and need help !! Me and my boyfriend have been together for 6 years now and living together for about 1 1/2 years. Through out this entire time we've lived together i've found him talking to girls on the internet. he says it's not a big deal because he's never been physical with anyone but me and I always forgave him because i love him so much and i know it's not healthy. Recently i found him talking to a girl from his work online caught him in the act of it. I packed a bag and went to my moms for the week. I love him so much and feel codependent with him. Should I stay or move out? I look around and think about it constantly. My entire life revolves around him I think. No kids. 1 cat. Any advice is welcome.