Guy friend?

Sorry to say this but you probably can't. When a guy likes a girl its almost impossible to go back to being friends. He will get jealous of your boyfriend, and upset and push you away. I'm truly hoping that I am wrong but I've never seen it happen except for when theres a long period with no contact. For instance.. if you and he had a fight and stopped talking and then a year from now you ran into each other and started being friends again.