WW, you say she is still your best friend, has stood by you through your d, has great supportive parents, wants children as do you, sounds like an animal lover as are you...there is still good there...maybe?  From what I read, the real problem for you is lack sexual attraction.  Was there ever an attraction?  It seems this is the sticking point for you, maybe?  You say your wife is great...a good person.  You are not bashing her on here to us (which would be easy to do.)  Maybe I'm not seeing the big picture as I only read bits & pieces & get lots of people on this forum mixed up, but it seems like you both might be able to make this work....I guess a marriage counselor will be able to help guide you to see if it is possible.  Good luck!