Again, I don't think it's about 'having a point', it's simply something that is. If I'm in pain, for example, I just want the pain to stop - even if there is no way for it to end. I don't want to die, even though I cannot prevent it. You make it seem like this is a choice.
It would be illogical to not desire these things, and also be illogical to actively pursue that which is impossible, and both are true and right at the same time.
What is the purpose of happiness? What is the purpose of any emotion?