to be used while weak

there is a worship song used in my church (and I know that this makes me a sinner, but I can't remember the name) with a line that says "you use the weak to lead the strong". Now I have heard this song MANY times and songs like it and verses from the Bible which say the same thing "God uses the weak to lead the strong", and this never bothered me before. before I would think of it from the point of view of God humbling the strong, reminding them of just how much they need God and others, by using the weak to lead them. As far as I know there is nothing wrong with that view (scripture seems to agree with it) but there is another view that I had never even thought of before! one Sunday I had had a long week (which went right a long with a long 3 1/2 months I've had) and I was just tired, ready for things to be better. I was weak. And then we came to this song (whatever it's name is) and for some strange reason I knew the song but when we got to "You use the weak" I totally forgot what the next line was! I was stuck on "you use the weak" as if that was the end of a thought. Instantly I thought "you use the weak, you could do this all on your own and I really don't have much to offer but you still come into my weak life and you work in me, and you use me, the weak". As soon as I thought that I heard the music say "...to lead the strong". What?! lead the strong? I can't lead anyone! I'm hardly holding on to MY situations! I can't help someone else! especially someone who doesn't think they need help. and just like that for the rest of the day I was stuck on the question of why God uses the weak (to lead the strong, to do anything at all) when they are weak?
yes, God has to break us down and take away everything that is "us" so that He can build us up with everything that is "Him". Yes we don't listen to God nearly as much as we should when everything is fine. But I just have to say that being weak hurts, just living life is hard, and to be asked to do great things for God while weak feels impossible.
So why does God do it?
Maybe the weak and strong are learning the same lesson, we all need God's strength to make it