I wonder if it's not writing but finishing something and having it judged that's the problem (a roundabout way of saying perfectionism). If it is writing--which I doubt given the fluency of the prose in your question--perhaps you would make a good counselor or coach or salesperson: someone whose job involves listening, influencing, and verbal improvisation.
It could be that you draw your energy from interacting with people (and learning) and you should look for jobs that have a significant component of that.
I think most jobs will reward learning (at least learning that leads to excellence in execution not just an accumulation of facts) so I would focus less on learning as you can normally work that into most jobs you take on.