Standards

Ok, I've been seeing this guy for awhile now. I'm the kind of girl that's considered the "good girl". I don't go out to clubs, drink or smoke. I've only had sex with 1 guy and we were in a 3 year relationship. I've met this guy Im seeing now a couple months ago (maybe 7 or 8). I have such high standards but I don't know where they went when it comes to him. We always have sex in his car nowhere else. We use to go on dates every weekend and we don't anymore. We talk everyday but that's not enough. He doesn't know I have a problem with this because I make it seem like it's okay with me. I thought about what if has a girlfriend but I know for a fact he doesn't. I don't want a relationship but I don't want to keep acting like this is okay. What should I do?