MAJOR trust issues and anxious about people being behind me

I swear I have the worst trust issues, EVER. I don't trust anybody, not even my family when they say that they love me or whatever.

If I get into a relationship, (which I doubt because I think I will always be alone) then I wouldn't be able to cope with it. Even if I knew them for months and want to get a house together, I wouldn't be able to sleep at night in fear that I might get assaulted or something, even though they would tell me that they're genuine.

I feel really bad, and feel like a stupid hypocrite because I always expect other people to trust me even though I never trust them....

Also, I am ALWAYS looking back if someone is behind me or walking behind me. I am always thinking that they're carrying a knife or something and will try stabbing me, especially if it's at night. Sounds completely ridiculous, right? Well, I am a ridiculous person after all. :(

I don't know what's caused this. I have never been abused or anything in my life. However, I was bullied in school and was back-stabbed constantly, so I think that may be the reason? I don't know why I have a problem with people behind me, though. If someone is standing behind me, I ask them politely not to as it makes me anxious.

I understand completely the behind you thing. I can't sit comfortably in a pub or cafe unless I have my back to the wall and the room in front of me. No specific fear, just a creeping dread of what's there.

"I don't know what's caused this. I have never been abused or anything in my life. However, I was bullied in school and was back-stabbed constantly, so I think that may be the reason? I don't know why I have a problem with people behind me, though. If someone is standing behind me, I ask them politely not to as it makes me anxious."

You have nailed it right there, and you have enough front to ask strangers not to stand behind you, you're going to be OK.