Hi i was just curious what caused some of harold's issues? Someone on another website told me that his not going outside may have been caused by the evil in those woods that that may have made him afraid to go outside.

 Also i don't think some of the stuff laura did to him did him any favors.

Ben:  "We've laid in a gala reception for your fair-haired boys tonight.  All of Twin Peaks' best and brightest."

Jerry: "We're holding it in a phone booth?"

"I thought you were different. You made me feel I could return to the world and find something decent and pure. But you're just like all the others. You lie, you betray, and then you laugh about it. You are unclean. You have contaminated me."

I think these words in the infamous ketchup-dispenser gardening tool scene are pretty explanatory... Something happened in Harold's past (in Boston?) that made him lose all hope in humanity and is what caused his isolation... They don't say what happened to him, but my guess is a combination of things, problems with his parents, with school, with someone he loved and abandoned him, a friend who he trusted and betrayed him... I also believe that Harold's condition has been there for many years... I don't think there's anything supernatural about Harold's issues other that those issues make him vulnerable and weak against the darkness that exists in Twin Peaks... He's the perfect candidate for becoming a host of an spirit.. Weak, full of holes, etc.

There was a fiish..iinn the percolatrr!

Harold was agoraphobic. People don't choose their phobias. My guess is that something traumatic happened to him at some point in his life. Once his fear became too out of hand, it began to control his life and he completely cut himself off from the outside world as a method of avoiding what it was he feared.