If I were to give one tip to anybody thinking of leaving a toxic person. it would be:
Get an answer machine.
The answer machine has been an absolute blessing. Not only can it filter out the toxic people in your life, it can also handle flying monkeys for you and collect evidence of the behaviour. I cannot begin to say, how many calls have been discontinued, once people have struck the answer machine. Some people do try to get round it. I had a few occasions where an attempt was made to talk through the machine to me but at least I had evidence.