My ex Is moving back. Problems!?

So last year I went out with this guy that me and my best friend liked. He had always sorta liked the friend but after she turned him down a couple of times he stopped asking her. I started liking him a LOT and then he asked me out and I of course said yes. Then my friend started liking him and she got really jealous it caused a lot of problems then. and even more when he dumped me. And asked her out about two weeks later basicaly me and fy friend always had issues of jealousy and stuff up until recently becaise i was waus so upset just thinking about how he dumped me for her and she didnt even care but they broke up and ut at the end Of last year he moved to deleware we started texting and we sorts kept in touch but then he started telling me that he didn't was t to talk to me and I had no idea why because it was so sudden so I finally just got tired of worying about it and forgot about him but he was only moving for a year and he is moving back this summer and the friend says she is gonna be friends with him but I have no idea what to do because I don want to have anyors drama or feelings for him a d I can't stop the friend from being his friend because I wouldn't do that and plus they have been friends since childhood until he stopped talking to her in the middle of the year so my question is what do I do since I am going to be exposed to h a d probably will end up talking to him a couple times also sorry for the lack of punctuation I'm typing on a iPod and it's hard please help