Is it childish to delete him on Facebook?

[flower]

this guy I liked, I thought he liked me back we've been talking since last year. only then he tried making me jealous by obviously flirting with this one particular girl in front me often. then when I told him I was seeing someone he said he felt jealous. now he completely ignores my very presence and I'm done with the games. I haven't contacted him in a month and he's so proud of a person I know he won't bother contacting me. I want to unfriend him on facebook but I'm afraid that will just make me look immature. should I just keep him on my friends list, post happy pics & statuses like nothing happened while ignoring him or just delete him?