Inlaw holding the wedding budget account tensions please advise

Hi everyone. We have looked at about 10 venues and are struggling to pick one but my fiancees parents have an account for our wedding that various family members have contributed to for us. The problem is her mother doesnt like me and is "in charge" of the account.


Her mother insists that she just sends us money for the venue deposit (and other things as we need them) and put it in our name rather than just giving us the account or putting it in her name since she holds the money. She is already inviting people without asking us first and really making it "her" wedding. She also says they are keeping any left over money so we cant do a small wedding then use leftovers for house deposit etc
I never really see her mother and my fiancee wont "stand" up to her. If i say anything there will very likely be a heated debate and expect the fund being taken away i.e. her mother will spend it herself or worse. What is the normal way for this to work? Surely parents would send us all the money for us to use on the wedding as we please like responsible adults? How does tax work in this situation? Am i being unreasonable? I wont even be able to book honey moon or stag do etc without her mothers "permission". I dont want a venue deposit in our name either because if something happens we dont have the money and she could use it to manipulate us. Please help. Thank you