I used to isolate myself at work too. I could not stand to be around all the back stabbers that were climbing the corporate ladder.I ended up getting fired because of my paranoia.
I believed they were all out to get me. I would miss days of work because of this.In a way I feel relieved not having to be around them any more.

Best wishes in getting through your problems. You should probably seek professional help. At least it might save you from losing your job.

Sincerely,

Sardean