I need help

Ok so the other night my SO and I were talking about how we want to do things once we get married. The big thing is bank accounts, I work but I don't make a lot...he's military and got money for his injuries in Afghanistan...and he was telling me that he's the traditional type once you're married you combine your accounts, which I agree with , but not because he has money. I don't care about money I use it for important stuff and that's it. But! Apparently his mom is over there saying he needs a prenup and he needs to protect his money! I have never given her a reason to not trust me or show her that I'm in the relationship for money...the only thing I would want him to do with that money is save it or down payment on a house...I thought his mom and I were close but I was wrong apparently and now I don't know what to do.