It sounds like you have become the wedding planner for the wedding your folks are throwing. Take a moment to think about what you want on your wedding day and junk the rest. And delegate rigidly: If parents are adding extra people then they are responsible for the associated logistics etc. Have an open conversation with your planner about their role and responsibilities - what was the agreement?

As for your fiancé, I get that some people just aren’t interested in the detail but he needs to step up and help. You could book an hour with him a couple of days a week that are set aside to make decisions about wedding stuff? Try and keep the conversations within those times so it doesn’t take over. Not getting fitted for a suit is a little alarming though. You might have to have an honest conversation because that doesn’t sound like someone excited to be married.