Forget lawyers, forget the police, move somewhere else.
There is no realistic alternative, and to not abandon a rented property makes no sense.
Emotional thinking will sink you, and you'll probably lose custody of your kid.
Make a choice, keep your rented house or keep your kid (and sanity)?
You've been posting this same thread for the past 5 years, and nothing has changed, because it's too easy for her to find you.
Nothing will stop her, my former misses in the UK is still at it, 14 years later.
Their reason for living is to hate you, and nothing you can do will change that.
But you can move somewhere where she can't find you, and the police won't be bothered looking.