Throughout our lives we encounter many people in our lives - some who inspire us to dream like they do, some who we even dare to share our dreams with. As much as this hurts, remember that not everyone who begins the dream will stick around to see it through. It doesn't make them bad people, neither does it make you a bad person. It's not necessarily a bad or a good thing - it's just that some of our shared dreams may only be meant for someone else's season; likewise, someone's dream may only involve you for a season.
There's no shame in that, and there's no reason to feel bad about it either. We keep dreaming, working hard and fighting to see our dreams through. Then we go on dreaming, even when we're dreaming alone.