I should learn to mind my business!

What's up with me today!

I am so angry with a 'friend' right now.I keep trying to search myself to be sure that I am justified,because according to the women's fellowship I attend, when you feel you know too much, that is pride!In trying to make her see sense / correct/talk to her,I overanalysed to make sure I was not proud. We all know GOD cannot stand that.I have a long history with this friend, I run a business and she feels that when she wants to use my services, she shouldn't pay because we are friends. Mind you, she is not asking for a discount, she believes I should not be charging her at all.
I had to see her today because I felt she was beginning to misbehave, without caring if she is hurting anyone (we are part of a team of 6 women of which she is the leader,and most times she takes decisions without checking with us,there is no form of accountability). Before we met today, I had to prepare oh, listened to Cd's on discernment, asked GOD for wisdom, asked myself if it wasn't pride in feeling I should give her a piece of my mind etc.
She is that......., so I had to do all these things.After the meeting, there was an ache in my heart, i felt very stupid, felt like I wasted my time and regret that I didnt mind my business.
The bible says when you know what you ought to do and don't do it ,it is sin especially when it comes to been your sister's keeper.Should I be glad that at least it is on record that I had spoken to her,I was pained though as there was no remorse whatsoever, It almost felt like I was talking to a stranger! Enough said.
I just pray that my head always accepts correction and I shouldnt let anyone cause me to miss the mark, which is my focus on getting to Heaven!