Blocking you is about power and control. They want you desperate for them, to want to chase them, to be prepped for when they come back to use you and make you grovel for the sad breadcrumbs they offer in the idealizing cycle (the very short one). So yes, its about power and control. Its denying you contact which you still want. 

Everything is a game with them. Everything. Good or bad. Its a game. For their amusements and benefit only. You wanting to maintain that small amount of contact is part of the trauma bond. Breaking it is important but hard. So reaching out for help is important. Having a person there in real life bringing their support and clarity to your healing is a big help. It can make all the difference.