Friends help each other. Care for each other. If she thinks that you are her friend, the nice things you do would be seen as a friend caring for each other. If she do nice things back, means that she is being a good friend, not "keeping your dream alive". It is on you deluding yourself into thinking that whatever nice she does, have to do with romance and not friendship.

If she has explicitly told you that she only wants to be friends, she is not keeping you to feed her ego, she is keeping you as a friend. Because people care about their friends.

To draw a parallel, is like that girl who is nice and friendly, that likes what you like but that you don't find attractive. And you enjoy her company, but you would never date her. Well, you are that girl for her. If you are not ok with that, walk away, don't tell yourself that "it would change in time". Because the change would be that she finds out that you didn't see her as a friend and would feel betrayed, hurt and deceived since she sees friendship as something valuable and you just told her that for you her friendship is worthless.

And that is why many women feel angry when we read guys complaining about "friend zone", because we have been that friend who was there for some guy just to be told that our friendship is worthless. Because we thought that there was a connection that never was there. And we explicitly told him that we only wanted to be friends and he told us that he was ok with that. He was the one who lied. We never said, if you do things for us, someday we would see you as a boyfriend. We explicitly said "only as a friend". It is not our fault if men lie to themselves. Or don't value friendship with women.

Try to see it from the other side and maybe you'll get it. We are people, not dreams.