Just looking for advice

OK so my MIL is getting on my last nerve.. a small bit of back story: she tries to control everything with money and I’m am very independent so we clash all the time. We have clashed before with regards money and me not wanting to be financially dependent on them to pay for things in our home. Me and my husband both have very good careers and although it might take us longer to get the house they way we want it, I like that we work for what we have. But my mother in law never respects when i say no. Her husband comes from money so the would be very comfortable. When i say no to her, she has gone as far to say her husband wont be happy about that and will need to talk to me about it… i am 35 years of age not 16…..
My husband thinks I’m over reacting at our latest clash of heads but I don’t think I am. We are having my daughters christening in one month. I am having it at home because I want a nice small gathering of IMMEDIATE family and CLOSE friends. She hated that we were having it at home as it restricted the amount of people we could ask and tried to get it moved to a restaurant in the city which we refused. But she said as her and her husband are paying for it she feels they have a right to have a say… I informed her she would not be paying for my daughters christening that me and my husband will be paying for our daughters christening. They did the same with his brothers girlfriend before they broke up and now the call her a gold digger. anyway she has gone ahead and invited 70 people to the christening and invites have gone out.. I have invited 5 outside of immediate family. Between family and guests we will have 100 people at our house for a CHRISTENING not a wedding… she is now saying how I’d be better off changing it to the restaurant like she originally wanted.. I am being stubborn and refusing to move it as I feel if I do she is always going to force my hand. I am also refusing to let them pay because if I do I feel like her and her husband will do this again and again and I really can not keep going through this every time there is something on for my daughter. And what of we are lucky enough to have more children. This christening is going to cost us thousands. Do you think I am over reacting and should I just let them have the christening they want.. I am so upset… I can not do this for the next 18 years….

My husband does try rain her in sometimes but he doesn’t get why I refuse money he would be happy to leave her to it for a quiet life. It is really starting to put pressure on our marriage.

Just looking for advice