I know this is super long, but...
I think the only reason that people wouldn't want to go to heaven is that they don't actually know what heaven really is or what it will be like. (Really we won't know what it will feel or look like until we actually get there, but we are given information on the nature of Heaven.) Many people think that heaven is just a place where there's clouds and harps playing infinitely, but thats not what God describes it as. In fact, in the book of Revelation, there is actually a physical description of heaven, it even tells you the dimensions of the city and the material Its made out of, go check it out, it's really interesting. But more importantly, it's described as a place with no more pain, sadness or suffering, the relationship between mankind and God will be restored to the way it was meant to be, the way it was before Adam and Eve sinned. Back when man and God actually walked and talked face to face.
I'm not sure what your friend's thoughts are on Hell, but people often have a lot of misconceptions of the other side of the coin, as well. As for Hell, I've noticed that a lot of people I've met seem to think that they will enjoy it more because of the people that they think will be there. We are told a lot of lies in the media regarding what hell is like, sometimes it's depicted some kind of waiting line where everyone gets bat wings, or a fiery rave party where people hang out for all eternity. Honestly, it almost makes my heart break when I hear people say they want to go there. The truth is that Hell is a place of torment and solitude, there is no enjoyment of any kind there, because it is devoid of God, and thusly, everything that's good. This is a pretty scary concept for anyone who's a non-believer and I wouldn't recommend explaining this to your friend until you progress further on in conversation.
As for your friend, I know all too well how hard it is to try to reach someone who doesn't want to receive Jesus yet. But you have to remind yourself that she's God's child even if she doesn't acknowledge it yet, and He says that it's His will that none should perish, but be united with Him. And as hard as it is to accept, maybe it will take a long time. Maybe someone else will lead her to Jesus (its the most frustrating thing in the world to wait for, but it's what has to happen, sometimes). But do what you can while you can, and let God handle the rest from there. Personally, I recommend reading C.S. Lewis's "The Great Divorce" and the "Last Battle". They give an incredible perspective on heaven and perhaps you can recommend the books to your friend. If she doesn't want to read them, I still guarantee that you will learn a lot from them, and perhaps you can share some of the stuff you learn with her in bits and pieces.