Struggling

So lately I've just been really hung up over an ex.  It's weird because he's been out of my life for so long because I kicked him out of it and then cut off all communication but then he just sort of slipped back into it because I saw him once and now I can't get him off my mind.  I don't miss him in the love way, I miss him in the genuine way, like I miss talking to him all the time, and miss having that person to talk to about whatever whenever.  I don't miss him in the way of wanting to get back together or anything. 
Now, he has a new girlfriend.  And it's not like I'm jealous of her or anything because I don't miss him like that way, but I still wonder if he ever tells her about me or anything, which I don't understand why I wonder about that.
And, on top of all this:
I keep telling myself I don't need a guy and I shouldn't want one but one but I still do.  And I want to just be free but at the same time I want to have someone there for me.
I don't know what to do about any of this. 
Please feel free to give me advice, because I'm definitely open to some tips or even just some reassurance that this is all normal and I'll get past it.