OP, I also think it would be a good idea to leave your mobile when you leave.
I say this because he may have a 'find my phone' app or similar on it so that he knows exactly where you are.
Get yourself a cheap new mobile with a new number so you can give your new job and trusted friends the new number. (Don't give your DM the new number. You can call her when and if you're up to it later)
If you leave your phone, he can't phone/text you, so you won't need to 'avoid' calls or dwell over texts etc.
You won't be constantly worrying about whether he will call or text either.
It takes away his power to continually bombard you with love bombing or threats. It takes away his power because ALL his 'power' is 100% dependent on him being able to contact you in one way or another, either in person physically, verbally over the phone or by a written message. To make you feel 'guilty' , 'ashamed' , 'weak' , 'dependent', 'sorry for him' etc etc. ALL are designed to force you to do what he wants, by whatever means he can think of.
Trust me, you will feel a LOT better when he cannot contact you.
And as far as his business is concerned, there's nothing preventing him from sorting that himself ! He doesn't 'need' you for the business, it simply suited him to use you for that because he could control you much easier when you couldn't be 'influenced' by 'outsiders' 
So, leave your phone, buy a new one.
Also, if you have a car, consider either buying a new registration number, leaving the car or parking a few streets away from your new house/ work, because if he sees your car either at home or at work, he'll be able to find you.