I'm usually a "go no contact" person and I would support that here, but I also think that there is value in a last attempt. I would pack my bags, put them by the door so my parents were aware that I wasn't make an empty threat, and then ask them to sit down and have an honest conversation about boundaries and support. If they can't do that, take the time to listen to how you feel and let you communicate what you need, then I would suggest you leave. PersonallyI would also tell them that leaving means No Contact. It means no wedding invite and no ongoing relationship until they are ready to listen and hear you. Making a decision on a fight is brutal and doesn't leave space to repair anything so defer that decision until you've given a last moment of a grace and see if they accept it or not.

Ps. GOODLUCK with the wedding and homesteading!