I'm so sorry you were treated this way. HE took vows, and obviously did not honor them. You do NOT want this man back in your life. You want the person you THOUGHT he was.
Nothing about you is what caused him to be this way. "Logic kicks in; the way he treated me at the end proved to me he was not my friend and did not value my friendship." That is absolutely correct. You can go crazy trying to figure him out, but all you really need to know is that he behaves like a sociopath. Such people are very good at disguising their true nature.
So you were taken for a ride. It happens to the best of us sometimes. If I were you I'd concentrate on getting legally disentangled as quickly and cleanly as possible and be grateful it was only 7 months, and not 7 years.