Answer:
I have joy in bringing two together, but darning my existence! My life hangs by a thread, filled with ups, downs and resistance!
What is often on the ground getting stepped on by others, but you donโt have to wash it because it never get dirty, in fact you couldnโt wash it even if you tried?
What goes up let's of a load and come back down
Used to keep prisoners silent and to make temporary repairs on cars.
What has to be broken before you can use it?
If itโs information you seek, come and see me. If itโs pairs of letters you need, I have consecutively three. What am I?