Y'all can fight me on this, but Dumbledore and Snape were not good characters. At all. Terrible people who were portrayed as good through Harry's eyes because he didn't know what bad was unless he were being killed by it (IE Voldemort)
This is the true significance of living in each moment and being fully present in your daily life. I'm certainly guilty of this, and I need to remind myself to slow down and take notice. Greet each day as a new opportunity full of undiscovered treasures.
You're doing both, Sarah. None of it will help you overcome your mental illness. Accept that she moved on and upgraded, learn why you lost such a wonderful person. Go become a decent partner for someone else. I won't beat her and use her like you did.