Excommunication: How to Lose the Game

I started off as Matilda, united Kingdom of Italy before dying, passed it off to my son and continued trying to go for the achievement. Unfortunately, this was the second son, the first one died from 2 year old infected wounds. This son isn't so hot; a bisexual, lustful, arbitrary and paranoid King. Despite abysmal diplo score, I try to keep everyone happy. The Crusades kick off, I put in the most score and bestow the Queendom of Jerusalem onto some distance niece because I don't want to be called into 20 wars I can't win later. When I get home, someone accuses me of sodomy, and that's when the game ends.

Why? You see, my relations were at -2 with the Pope, and someone didn't like me. I didn't get any relation bonus from the successful Crusade.

The Pope comes in and excommunicates me. The Emperor imprisons me, strips me of all my titles, including my capital, and leaves me as just a count in Padua or some other nowheresville. Once all my lands are stripped from me, he executes me.

Game is essentially over; I'm sure it's recoverable, but as far as achievement runs go, it'd be faster to just start over as Matilda again. I found it surprising, and from a gameplay perspective unfair, that the Emperor was able to revoke all but one of my titles, including my capital of Florence, as well as execute me, for have a -2 relation with the Pope and a guy that didn't like me.