seeing impermanence deeply will allow you to let go deeply. Hence lowering your attachment to things. This means that you will not get hurt when those things you are attached to pass away (as they eventually will). However this does not mean you will not have compassion or kindness- far from it- when your troubles have faded and when you see those same troubles in others there will be more space for compassion. All your sufferings are impermanent- hence it becomes easier not to get caught up in this, if this bit of wisdom is working deeply in the mind. Noting impermanence of everything in your body and mind you come to the understanding that there is no self, but a collection of process- hence death looses its meaning, it grip over you- there is no one to die, just processes continuing in a different direction. You can also break down 'big' concept such as 'old age', 'sickness', seeing how when we label something, the label brings with it certain values, over and above the experience of phenomena. We can see that the phenomena itself is not as bad as the label implies. We being to see that these labels aren't fact, but just thoughts trying to make sense of reality but not quite getting there, often coming to wrong conclusions and projecting 'facts'on to experience which simply aren't true. So the existential questions of old age, sickness, death and suffering gets answered.