My understanding of her group is that they are not exactly representative of the Episcopal Church. Certainly, there are groups such as the ACNA that do not agree with this position and thankfully so. However, this does represent an example of what happens when things go off the rails. Our Anglican friends on this forum will not like this, but I am going to say it anyway. From the second the Church of England split off from the Catholic Church on the moral issue of marriage, this moment was inevitable.
After all, why is one moral teaching any more sacred than another? Why is one aspect of the faith any more sacrosanct then another? If marriage, which is an icon of the life of the Holy Trinity, can be reinterpreted based upon the whim of an earthly king, why not the priesthood, homosexuality, contraception, abortion, confession instead of general absolution, the papacy, etc.?
All you have to do is find an excuse to give up on one little thing and someone else who follows on will find a way to rationalize getting around the next, and so on. Each generation just gives an inch here and an inch there based on the times they live in; and in a few hundred years, the Church you have is unrecognizable to the Church which used to exist, and the faith you practice is irreconcilable with the creed you profess.
Members of The Church of England from 100 years ago would be shocked and dismayed to see the state that their church is in today. The unfortunate truth is that the die was cast a long time ago.