Honestly mate, you need to focus on the cars. Listen to your dad, the people in your town and your old co-workers. They are trying to help you.
Some people on here are taking the piss, but it's clear that you have a genuine mental issue and stirring you up or ridiculing you isn't really a nice thing to do - it's easy sport, like picking on a disabled kid.
Try this - don't post anything other than car stuff for 1 month and see if it helps. Everytime your mind goes to some of that other stuff, bring it back to car stuff. Only car stuff.
Try it for 1 month.
And if everyone else could leave him alone it would be nice - imagine if it was your son or daughter with these issues.