Paranoid Thoughts

I have been struggling with a low grade depression since I was a teenager. I have always been able to cope with the symptoms by myself but when I hit my early twenties, that changed. I went through a lot of transition (marriage, moved out of state, graduate school, financial problems, thyroid cancer). I was very depressed but did not talk to anyone about it. Instead I just suppressed my feelings.

Now that I'm in my 30's, I am at a standstill in life. Anxiety and depression have paralyzed me. I'm unemployed (quit my last job because of stress) and have no ambition to work.

My counselor said I have an adjustment disorder but gave no other diagnosis for the other axes. I am concerned about this because, during my last depressive episode I had paranoid thoughts about former clients coming after me for revenge. I believed cameras were in my smoke detectors at home. I constantly peeked out the window and monitored who was coming down the street. I Could not sleep well because I had to stay up and protect the household against these former clients.

The cameras in the detectors, I believed, were put there by the former occupants of the house to monitor my husband and I had to check all of them occasionally to be sure that they weren't bugged. These thoughts lasted about 5 months and subsided as my depression lifted.

I now realize that these thoughts were unrealistic but what can be the possible cause? I believed they were legitimate thoughts at the time and this scares me. Depression and anxiety run in my family and my great grandfather was institutionalized(not sure what for) so this makes me very uneasy.

Any possible thoughts on what these paranoid thoughts could mean would be appreciated.