I just can't said these things. .

Okay,this is my weakness.

I can't help myself to say NO or YOU CAN'T USE THIS COZ IT'S MINE.
Or maybe PLEASE PAY BACK MY MONEY YOU BORROW BECAUSE I NEED THEM NOW
Or PLEASE PAY YOUR PART OF THESE STUFFS WE BOUGHT

I am afraid to said all those..
Because when I did "hutang" my friend or I use their money first to pay things,I will try my best to pay as soon as I can.
I feel ashamed if I pay them very late.

So guys,any tips for me to be more confident to say those words?
I am tired of being used sometimes but I don't know how to gather strength to said those words.
Oh God,I just can't!!!!

I wish I am like some other friends that will ask confidently from others what they are supposed to claim.
But me? I am always like this.
Guess that's why I always being the one that "kena pijak kepala".
Huhuhuhuhu.

Help please anyone. This is my biggest problem in life.