Guy i'm seeing confessed he still has feelings for ex?!?!?!?!?

[helpless]

So i've seen this guy for almost 2 years and we both like each other very much and we're planning to go for a date. And then this one day i was like chatting with him and we were talking like normal. Suddenly a conversation about his ex came up. The ex im talking bout is his first. And this guy will be my first if things go right. So we were talking bout his ex and he suddenly said that somewhere deep down in his heart he still has feelings for her. And then i asked him what would he do if she were to want him back and he said i might just go ahead with her. At that instant, my feelings just died. I dont know how he could want her since she cheated on him. Im so confused. Should i just stay away from him or should i just go on this date? How do i stay away from him? I've never had a boyfriend and im so emotionally disturbed by this.