I went through a similar situation.
Was in a major car accident.
Difference was, I still loved my fiance, I just couldn't remember why. It was like having this deep emotion, with no umph behind it. I tried to work through it, but I had no choice but to cancel our wedding, because I couldn't make that commitment being so unsure. That didn't go over well.
This is the thing though. People knew a person that I wasn't. They'd tell me about myself, but I didn't relate to that person's thought process. We shared a name, we shared a face, but who was he? It's like I woke up in someone else's body.
My brother once said to me, "You're a lot nicer than you used to be, your attitude is way different." That was when I realized, that the person my family knew, was dead.
Back to my ex, as I got to know her over time, she just wasn't a person I could see myself with for life. Like 90% of the time, she was the perfect woman. The other 10% of the time she had deal breaker flaws. I guess the old me could see past those times, but fuck that I can't.
As time went by, almost all of my memory has returned, I have all of the talents and creative interests I had before, but I still feel like a ghost.
Where I am now in life, was all based on someone else's decisions. Weird stuff.