You may never read this, but I have to comment.
You have not “failed as a man.” You have succeeded as a person, a human being, and (from what I have read here), you and your wife have succeeded in raising your son with real human dignity.
To those who commented with criticism, cruelly stating that your children would be better off without you, that the way you live life is child abuse, or asking whether you/your wife were “a lesbian now,” I respond by saying that real love is genderless, and their judgment doesn’t matter because you and your wife/family made this important decision together.
Love is not solely about our “personal plumbing,” whether those organs match or contrast, and what we get out of having sex. There are people who live a fully celebate life while in love, whether straight or gay, whether transexual or asexual, etc. Love is about the recognition one soul has for another. It’s about respecting and honoring one other no matter what. It’s about supporting one another in rough times, and celebrating one another in the good times… and it seems you have not only found that love, but you are demonstrating it.