Welcome Caspian.
Like you I also was an elder. I held this position for 5 yrs. then resigned due to the things I experienced. Drifted away slowly or at least tried to. Found out one of my daughters had been molested by an elder. You can imagine the resulting chaos. Due to this and my anger at the situation I was df'd. The advice you have read here about going slow-getting some counseling- seeking a support group are all very good suggestions.
As all of the advice you have already viewed here pretty well covers the situation I have nothing more to add. As you have read this will be a rough journey requiring well thought out decisions.
As time goes by if you feel safe doing so, revealing some of the reasons behind your crisis with the wbts will undoubtly be of great interest to others still in the org. that also have problems with the actions of the wbts.
Again welcome, wish you the very best in this journey.