I can completely identify with the first half of this. I have unsurmountable empathy and awareness of the world. I can express anything into beautiful words and paint pictures and scenes. I'll admit that. ...But when it comes to myself I feel absolutely incompetent.

But this is actually something I'm trying to work on. I've avoided my own problems my entire life for various reasons. Most importantly, I never learned or had an environment in which I could express my emotions and feelings and translate them into healthy thoughts and actions. So it's been something I just avoid. I'm known for being vague and "mysterious" in my own life.

The most important step in expressing myself in therapy has been to take ownership of what I'm trying to "translate." I've always replaced words like me and my with you and your. This usually happens when I'm explaining a way I feel and act in some sort of metaphor - yet another speciality of trying to get someone to understand. Saying personally possessive words felt really uncomfortable at first. It still does sometimes but I've started doing a lot more without thinking about it. But even now and then I'll hear a generalized word slip out (i.e. your, they) and I'll stop and rephrase it. It's definitely helping me at least understand my tendencies a bit more and think about how people might not always understand what I'm saying. If nothing else, it helps me be more aware of what I want to say and how I'm going to say it.

Not sure if any of this is your problem. But maybe someone will stumble across this and find it useful LOL