Firstly, assuming the world won't end soon, why does that make it not an issue? What if it takes a million years to figure out how to fix it?
Secondly, if you believe that it will take millions of years for our planet to become uninhabitable to us, you need a wake up call, but since the issue of climate change is considered by many to be political, I guess I'll have to avoid that topic here. If you don't believe we're affecting our planet, you're mistaken, is all I'll say. Closing your eyes does not remove the threat. I wish it did. I wish you were right. I really do.
And, sorry, but no, we haven't found any habitable planet. We've found planets that could potentially support life, but that doesn't mean they are ideal for human life. These planets are also thousands of light-years from us, so it's unfeasible that we will ever reach them. I won't say it's impossible, as many do, because who knows what we will learn about how this universe works, but I wouldn't bet on it.
You can believe what you want to, though. We will be dead before it happens, so it won't affect us. But that doesn't mean it doesn't matter. Some of us care about future generations. We are cursed to care about what has no impact on us.
Anyway, on topic: I believe that we are destroying our moral boundaries. We are greedy for more, it's in our instinct; nothing will ever be enough, because we determine the state of our being to those of others. The majority of us today are living in far better conditions than generations before us, and yet we still are not happy. Our material needs will only continue to increase with each generation as we strive for more. This will lead to our downfall.