I'm going to get my ex's car repossessed.
How does that make you feel?
I feel bad that I have to get it repossessed but she deserves it for how she has been acting.
That is a terrible thing for you to do. It is impolite to take vindictive action against an ex. You should just try and move on and not worry about the things that she does.
Hopefully this makes her feel sorry.
As hard as it is, she will get her revenge naturally and you are only hurting yourself by doing this. You should just move on from her.