Human beings are selfish and will continue to destroy Earth. (Religious people seem to be worse about this in my observation, because they believe gawd is going to come around and wipe it clean.) I think we need to take reasonable efforts as individuals to do the right thing and influence others to. This will slow the destruction and suffering resulting from it, but I don't think we as a species will stop ourselves entirely. There will eventually be a cataclysmic event to reduce or eliminate humans from the planet, and life will go on again as it has for so much of our history.
Despite knowing this, we should also try our best to enjoy life and make the most of our brains and energy to contribute to society.