Why was King Edward VIII's marriage to a Divorcee so opposed by the Church of England, when the church was founded on the basis of allowing Divorce by King Henry VIII?

I can't speak to the Edward VIII portion, but Henry VIII did not divorce Katherine of Aragon, nor did he divorce any of his subsequent wives. The marriage was annulled. More context can be found here from /u/quickspore and here from /u/rtarcher for more context about his marriages.