My girlfriend does not talk to me anymore?

I'm 22 she's 20. We've been together and living together for a year. We love each other and we never had too big of a problem with out relationship.

now all she is doing is play the SIMS game on my iphone to the point that she falls asleep without even talking to me. Another thing is that she does not talk to me much even when she is around me.

I still talk ALOT to her but she does not seem to care to reply. Yea sometimes we have little conversations but only when she wants to say something.

Ask her if she is tired of you and wants to move out.
wait for her to answer.
if she takes too long to answer you know the answer is yes