I agree. You held the ball in your court for a year and decided it was ok finally to be friends, which is fine. I'm not knocking you for letting time heal wounds but she was probably insulted you waited a whole year to respond and wanted to one up you or have what she feels is the last word. I'd let it pass. She chose to add you as a friend and chose to delete you, let her walk if she wants to.
So, so you think you can tell Heaven from Hell,
blue skies from pain.
Can you tell a green field from a cold steel rail?
A smile from a veil?
Do you think you can tell?
And did they get you to trade your heroes for ghosts?
Hot ashes for trees?
Hot air for a cool breeze?
Cold comfort for change?
And did you exchange a walk on part in the war for a lead role in a cage?