Giving my ex a second chance!

Met him about 2 years ago and dates for a year. Then all of a sudden he just disappeared. Didn't answer calls/text so I gave up on him. Last week we met up for closure and he explained his reason for leaving. Now he wants to give it another shot and I am seriously considering it being that he seems like he's a different man but I'm afraid he'll eventually go back to his same behavior and disappearing acts. What makes it harder is that this 2nd time around it just feels so pure and right. Help, I don't know what to do!