If you mum can't take it, will she do anything stupid?? since she love the animal so much, better think about it, or you will blame yourself forever.

If I were you, I will make a police report and hide. Don't let the animal know where you stay. If he used up money, he will find you. Maybe I watch too much drama, but base on logic, he will find you when he need money.
If possible, migrate to other state or country, but this required you to change job.