Feeling unsure about my soon-to-happen wedding, what should I do? Any advice helps

I (26M) am getting married within the next two months and oddly enough these last couple months have been the most unsure I’ve been about this relationship with my (26F) fiance. It seems like some of the things we struggle with never get fully resolved and are just put off for a few months until it’s an issue again. It seems like at least once a week we have some fight that really stresses both of us out. On top of this, her mother is very controlling and has made many comments in the past about how I’m a shitty person (literally every single one of my coworkers/ friends says I’m kind and fun to be around) and that we shouldn’t get married. Unbeknownst to me, her mother decided to take a poll among five other family members who all have major issues with their own relationships and all of them voted that my fiance and I should not get married ( I don’t think we should pay any attention to this decision for one because they don’t know how we feel for each other and two because it is certainly biased because her mother has all of these family members employed at their business and won’t hesitate to fire them). In this relationship I’ve had to deal with several nasty comments not about just me but also terminally ill family members. My fiance and I do struggle but I absolutely still love her. I have come forward with the idea of postponing the wedding but she wants to go ahead with it because her mother is paying for it ( I knew from the beginning her mother would hold the cost of the wedding over our heads and told her it was a bad plan to accept her mothers offer). I feel so drained with everything but I feel I would also have an immense feeling of guilt if I backed out. I’m not sure how exactly everything would play out but I’m sure it would be very ugly and if I’m being completely honest I’m scared. I have no support network near me and the rest of my family lives at least 10 hours away. I guess this is just one big rant because I don’t really have anyone to talk to that could be considered an outside party.

TLDR: I am unsure if I want to go through with my wedding due to some issues with my fiancé’s family/ persistent issues with my fiance. I do very much love her but I constantly feel stressed about the idea of our wedding day. Any advice helps

Reposting to fix an error with original post