Marriage is different for everyone. If you are religious and still believe that it holds some religious connotation, then of course you are going to look at celebrating the divorce as a sad thing. I think you really need to step out of the box though and understand some marriages are absolutely awful and sometimes violent at the end. If someone is being straight up abused mentally, verbally, or physically and they finally get themselves out of the relationship, why would you be opposed to them celebrating it? They've been dealing with some heavy shit for however long. So you have a problem calling it celebrating divorce and prefer calling it celebrating new life, but lets be real here, it's still the same thing.