What does "it's complicated" mean?

Hey guys I was reading the guy I like's profile page and on relationship status he says "its complicated" but were always flirty when we meet he still hasn't asked for my number or anything does this means he's attached or just confused? Thanks!
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+1 y
Thanks for d advice, met him today! Got so nervous thing is I never get nervous when I'm talking to him! We walked and chatted together but I'm nearly definite he ain't going to ask me out! So at least I know now and save me keep messing with my head.
What does "it's complicated" mean?
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