I mean, if the relationship can't survive the long term, why on earth would it be worth my time and energy for the short term?

This quote is referring to relationships. It is suggesting that if a relationship is not strong enough to last for a long time, then it is probably not worth investing time and energy into for the short term. It is important to make sure a relationship is worth investing in by understanding what it takes to make a relationship successful over the long run. If that doesn’t seem possible, then it is best to not invest too much time and energy into the short term.