My suggestions - did work for me:
1) Slow down gradually
2) Step down as an elder
3) Switch to another congregation (KH)
Point 3 was very important. Since we were very active and had very strong relationships in our former congregation, it would be very painfull to fade there.
My wife is still in, not active by now, but very social. So we moved to anther KH and from the first day I showed to all I am not here to talk to anybody and to make friends. I also stopped (actually did not started) giving reports from FS in the new KH. No one really dared to give me any counsel so far.... Its over a year by now we go to meetings maybe twice a month and its progressing very well for me. I told my wife clearly, that if elders will start being interested in me - I will be DF very quickly ... so she better doesnt seek any "help".
Moving to another KH - important step for succesfull faders...!
If you want to keep your marriage - be from now very very very loving and patient husbend, more than ever before.
Albert