I think you need to find a sex therapist. Perhaps go by yourself the first time and see what they suggest.
I am not suprised you couldn't 'perform'. Jeepers it can be scary enough the first time when lust and teenage hormones are involved. Where lust doesn't naturally exist it must be even more difficult.
I think what you are experiencing is very normal considering your situation. I imagine fear must be a large factor for you W as well. You say she is a doctor....I am assuming a medical doctor...that doesn't stop her being scared. In fact it makes running away seem very understanding.
Both of you got married knowing the situation. If you find a solution your wife may well be open for discussion.
Have you come across a book called Peace Between the Sheets? You might find it useful. Have you done any other reading around this subject area? The trouble is really, you can intellectually understand the problems, but emotions are involved which really complicates things.
Please, please, please go and find yourself a sex therapist. I am sure you are not alone in this.
Saffie me 46 H 46 M in 1986 D20,D18,S16,D13 H's A 01/05 to 07/06 H recommitted to M 07/06 renewed vows 09/06 Going from strength to strength