I think humanity will self destroy itself over the next few centuries as resources and fresh water supplies continue to dwindle and climate change continues to be felt, particularly in 3rd world countries, leading to all sorts of crises and increased warfare and misery. Eventually this all bites 1st world countries in the ass, who up to now have been cushioned from the very worst effects whilst reaping all the profits. Ultimately the human race and the planet can only produce so much energy and resources, and we have pretty much hit that limit already and demand more then what we can supply whilst simultaneously crapping up the planet we live on to further make it volatile.
There is a naive belief that this will be averted (i've seen this expressed by a LOT of escapists) by some radical technological breakthrough or that we humans will simply "adapt" cos rawr! we are humans! And we are too mighty and divinely made to be bought low by our fuckups. To me that's just wishful thinking and really placing all your eggs in a fictional basket by assuming something is gonna come along that is magically gonna fix the situation. As much as I'd love that to be true+humanity makes it into space, atm I don't see that happening anymore then serious space exploration, there's a good chance our species is going to die on this rock and be buried under forces we cannot control but arrogantly believed we could adapt to because we were somehow exceptional and special, our remains to be found millennia later by a new evolved race on earth or aliens, to be a galactic footnote in some distant museum as they tell fascinated alien schoolchildren of a cautionary tale of this foolish race from a planet called earth that saw disasters coming but always assumed something would come along to save them and so never bothered to actually take the necessary steps to save themselves.
If me and my friends somehow do survive the extinction event, it would probably be by some passing alien ship deciding to kidnap some humans as pets or curiosities before the race dies completely.