Why is it that everytime I talk to my ex-boyfriend ...

Hi,
There are several possible reasons (no offence, please):
1.  He is trying 2B nice 2u. 
2.  He wishes to give you a
     good feeling. 
3.  He is playing with you &
     with your feelings.
4.  He wants to keep you on 
     his waiting list (and if the 
     other relations he is trying
     fail, you'll be waiting for him).
5.  You want him so much that
     you don't read the real
     messages.
6.  He is simply a nice charming
     guy.
And there are sure some more possible reasons.  If he really loved you he would still be with you (in the first place) or return to you soon after realizing that he still loves you and is missing you.  As you know action speak louder than words.... if he won't call you 2 weeks after a friendly chat with you, that means more than any word. 
I realize you really love him and want him so strongly back so give him a chance, but (no offence please) I don't believe it will happend and better move on and find someone who deserves you. 
Best regards,

Because he's not really interested in getting back together. He's called a "user" because he's using you. He's behaving and talking to you like you two have a chance at getting back together but at the same time, he's going out and having fun, probably messing around with other people. With your current relationship, he gets to "eat his cake too." Does that make sense? I honestly think you need to move on. Find someone who will appreciate you and not keep you waiting while he's out looking for something different or better.