Pre-diabetes Metformin

There are days when you strive for more on everything to be perfect or at least as much as possible, the opposite happens, today was a day well for me ...
I had a discussion with my sister ... ended badly ... Now I feel HORRIBLE ...
The more I try to approach it I can not ... she feels that everything I do or say is to annoy and that is the least try to do ...
I'm sad ... she is my only sister and I love a lot ... and that anything or anyone can change ... or even days like these.