Have you thought about trying something else for a while - like spinning? It's not the same, but it will give you a great big endorphin rush - which can be very helpful in the dark world where running is not possible.

If you are wearing the heel insert you were given,  you might want to look into that too.  I was told that leg discrepancy is not always truly bone related and mostly superficial. It is different,  for most people,  from day to day since it is mostly related with muscle tightness ( if you sit , sleep weird ... ) For example, the discrepancy before and after a massage is mostly different, sometimes significantly. After few experiences, I am skeptical of inserts in general. 

Like @CompulsiveRunner suggested, I am still working on tendinitis in my left foot.  No running in the last few months.  I just got back to riding (indoors it's -1 today) and it has helped lift my spirits.  I had been working with a PT for a couple of months, but for unrelated reasons, I needed to stop.  It took me a while, but I progressed to where he allowed me to push through the pain.