Leading me on?

I started talking to my ex whom I broke up with almost a year ago. I let him know that I missed him and that I still liked him and he had said the same things to me also. Though I found out he was dating someone over the summer while he was telling me these things. Now he's single again and said he's "still talking to her" but he never confirmed in what way. I'm conflicted and not sure what to do as to whether I should stop talking to him completely or what. Help with any advice?