I feel like I want to go in with my head held high to tell her that I'm not going to allow her to have power over me anymore.

This^ is what made me think abuser. It doesn't sound like a simple good-bye. I guess it feels unresolved--as though the hope is that going through this will result in a feeling of closure, rather that it being a presentation of a resolved good-bye.

I remember when I was able to recognize good in my parents. I never had the desire to forgive their abuse, but the feeling when I was able to accept that there was good along side the bad, was very freeing. I couldn't separate from them as long as they existed in my mind only as abusers: the negative attachment was too strong. It was only when I could recognize the positive as well that the bond lessened and I could let it go.

I don't know the situation with your ex-T, but somehow your bond feels a bit similar.