Cut off all communication

Sociopaths use children as a cover for their manipulative and obsessed behavior.  Stalking and harassment can be done under the guise of "necessary" contact for visitation, etc.  Outsiders assume that the Sociopaths behavior is "normal" or "necessary" because of child contact, and so outsiders do not understand or recognize the way that the sociopath is manipulating their children's father. The non-sociopathic parent is victimized by excessive, unnecessary, harassing contact.

The sociopath will want to have contact with the parent of their children. NOT BECAUSE IT IS IN THE BEST INTEREST OF THE CHILDREN.  But because it's how they stalk, control and make your life hell. So when the children are older and the non-sociopathic parent tries to establish contact with only the children - the sociopathic parent will become angry. Because if the parent can communicate with the children verses her - she is losing control. And sociopaths fear losing control. So she will insist you must communicate only thru her. DONT GIVE IN TO THAT. If your children are at an age where they can communicate with you - then by all means communicate with them only and cut off ALL contact with the sociopath. Despite her threats, and attempts to hold control over you. Know that she cannot control you once the children have reached a certain age.  

Sociopaths will try to make life hell for you. Not only will they make your life hell. They will target your new wife or husband as well. They target your new spouse because of the jealousy they feel towards them. Once you moved on and decided to remarry or become involved in a serious relationship, the sociopathic realized that you are no longer concerned with them. The new person in your life means that they will not be able to control you for much longer. So what do they do? They target the new person in your life, hoping to make life as miserable as possible for them – in hopes that the person will leave you. 

The sociopath may or may not want you back. But the reason that they run off or try to run off any body that you maybe come involved with. Is because that person poses as a threat to the sociopath. The sociopath loves control and fears losing control. The sociopath  will do whatever they can in order to stay in control. You and your significant other may have to go through years of hard times, drama and stress. But if you stay strong and you refuse to allow the sociopath to interfere in your lives and cut off all contact. Your relationship will be not be damaged by the sociopath. 

The sociopath cannot get away with their tactics forever. Always remember that. They will be exposed eventually... Whether it's when they're 45 years old or when they are 75. They will be exposed. One thing to look forward to is knowing that the sociopath will eventually die. They live a reckless lifestyle, most abuse drugs. So their survival rate is usually not good