You can't hate yourself even more, you have to get up everyday and live for you. You have to be happy and move on for you. I know it's the cheesiest thing someone could say right now, but trust me, it's what is best. If you need closure get it. Any kind of closure you need - if you need to confront your ex and tell them that you can't continue doing this anymore than do it, if you need to go out in the middle of no where and just scream and cry then do it. Whatever you need to do to feel better about yourself make sure you do that. At this point of time the small things that you do to make yourself happy is what matters the most.
It's understandable, when someone has a part of your life like that it's normal to be confused even after they leave. Even if it's years later, you can still be confused.
In all seriousness. If it's best for you, and as hard as it may be then you should probably block him, or tell him that you can't do it anymore. Relationships like that are definitely not healthy.