What "self" are you expressing when you say you want to express yourself but don't want that self identifiable? That's a pretty big contradiction. You can't eat your cake (post thoughts that refer to experiences that could identify you) and have it too (not have anyone know who you are).

If you're really worried, create a pseudonym and post under that. Probably a better option is to take the bull by the horns, post as yourself and use that as an incentive not to post stupid things.