That's my position in the case of a nuclear winter as that's fundamentally unsurvivable, so why bother right? However in the case of a total breakdown in global trade I'd be more willing to try stick it out.
Looking back at the historical record the collapse of the bronze-age civilization is the closest parallel I can see to what I would imagine will happen at some point to either us or our children. The best hypothesis I've seen on what happened there is there were a bunch of inter-dependent societies that traded with each-other by importing raw materials and producing finished goods and trading with others. There's evidence of drought over an extended period which led to both famine and migrations of people in famine affected areas to other locations in search of food that also brought people into conflict with each other and some evidence of internal uprisings from social unrest. Any one of those things in isolation seems not enough to take everything out, but when all occur at once it seems it caused a breakdown in trade which was sufficient enough to reduce the complexity of the society to the point that individuals that had come to rely on that complexity weren't able to survive it going away. There is a great talk on YouTube called "Social Collapse Best Practices" given by a guy who lived through the collapse of the Soviet Union and he compares it how he thinks the US would fare in a similar situation and gives practical advice as he sees the same structural forces at play that brought about that collapse. This talk was given in 2009. I've been digging back as far into the past as I can on people giving doomsday predictions and back-testing what they say to assess accuracy, and a very clear trend emerges that everyone who focuses on the fundamentals is largely right.