WHY DID HE DO THIS?!?

My ex broke up w me seven months ago, it was bad and we hadnt spoken in three months. Out the blue, he has been staring at me, watching me and trying to get into my conversations. Then, he finally came up and hugged me and asked if we were alright and just repeated , "I'm fine with it." A few times. Later we talked, he took the time to explain himself and then he made a few jokes and told me a bunch of rand ok stuff. he said he had to gp to bed but he kept it going a little longer. I dont get it?