Honestly, my first thought after reading your post is that you're dealing with 'self made attachments'. Self made as in created by you unconsciously through anxiety or fears experienced while conscious. I've spoken to individuals and read several accounts of this happening.
I've recommended William Buhlman several times on this site before and would recommend you read a section on his website called 'Keys To Control'. He mentions encountering frightening beings/forms and also explains that they are a personal manifestation of fears, obstacles, etc. It is also an opportunity to confront and conquer fears, limitations, blocks, etc. He advises to confront the form with love.
Here is a link to his site and the section Keys To Control:
http://www.astralinfo.org/obe-keys-to-control/
Just wanted to give a different perspective to your issue. I wish you the best.