Confused

So I have this guy friend that I've been friends with for years. We have talked as more than friends before but never did anything about it. We both kinda new the other liked the other. Years have gone by and we have had sex but just random times. First time drunk but the times after that we were sober. He had been going through tough times in his life and has asked to ride around with him and he just vents to me and tells me he doesn't talk to anybody else about it. And I love being close friends with him but then at the end of the ride he takes me and pushes me against the car and starts making out with me and wanting to have sex. I turned him down because it would just make things confusing. He says he's confused and wants to have a relationship that starts out as best friends and goes into something more. But never says its me.  Everytime after we have a moment like this We stop talking for some reason for a couples months. What does that mean?